African Black Beetle
Pest — Affects: Corn, Potato, Lawn, Strawberry, Seedlings
Plants collapse or fail to establish as roots are severed. Lawn develops dead patches in irregular areas. White C-shaped larvae found in soil when beds are dug.
Cause: African Black Beetle (Heteronychus arator). An introduced pest. Found across southern and eastern Australia, particularly coastal areas. A consistent problem in gardens adjacent to lawns.
Season: Summer, Autumn, Winter
Natural remedies: Diatomaceous Earth
Alternaria Leaf Blight (Carrot)
Disease — Affects: Carrot, Parsley, Parsnip
Dark brown to black spots on carrot leaves, starting at leaf margins and tips. Spots may have yellow halos. In severe cases, entire leaves die and the crop looks scorched.
Cause: Alternaria dauci. Fungal disease spread by infected seed and water splash. Found across carrot-growing regions of Australia. Worse in warm humid conditions.
Season: Spring, Summer
Natural remedies: Copper Spray (Copper Oxychloride)
Anthracnose
Disease — Affects: Tomato, Capsicum, Bean, Mango, Avocado, Cucumber
Sunken circular lesions on ripening or ripe fruit, often with concentric rings and salmon-pink spore masses in wet conditions. On beans: dark sunken cankers on pods and seeds.
Cause: Colletotrichum species. Spread by rain splash and water. Found across all of Australia — common in the warm humid conditions of coastal NSW.
Season: Summer, Autumn
Natural remedies: Copper Spray (Copper Oxychloride)
Ants (as a garden problem)
Pest — Affects: Most vegetables, Seedlings
Ants farming aphids and scale insects, actively protecting them from predators. Disturbed roots around seedlings as ants build nests. Rarely cause direct plant damage themselves.
Cause: Multiple species including Black Garden Ant (Iridomyrmex spp.) and Green-headed Ant. Found across all of Australia. The ants themselves are less the problem than the pests they protect.
Season: Spring, Summer, Autumn
Natural remedies: Diatomaceous Earth
Addressing the aphid or scale problem removes the reason ants are there. If ants are a structural issue around garden beds, a physical barrier like a water moat or sticky tape around pots interrupts their access.
Aphids
Pest — Affects: Tomato, Capsicum, Beans, Lettuce, Cabbage, Roses, Citrus, Broad Beans, Kale
Clusters of tiny soft-bodied insects on new growth, shoot tips, and undersides of leaves. Affected foliage curls, puckers, or yellows. Sticky honeydew residue on leaves, often followed by sooty mould. Ants farming aphids are a reliable indicator.
Cause: Multiple aphid species including Green Peach Aphid (Myzus persicae) and Cotton Aphid (Aphis gossypii). Found across all of Australia — ubiquitous in vegetable gardens on the Mid North Coast year-round but worst in cooler months when natural predator populations are lower.
Season: Spring, Autumn, Winter
Natural remedies: Soap Spray, Neem Oil Spray, Garlic Spray, Chilli and Garlic Spray
Soap spray is my first call for aphids. Cheap, fast, and it works. The key is hitting the undersides of leaves where they cluster.
Avocado Thrips
Pest — Affects: Avocado
Scarring and russeting of avocado fruit skin, particularly around the stem end. Rusty-brown surface blemishes. Does not affect eating quality but reduces market value for commercial growers.
Cause: Avocado Thrips (Scirtothrips perseae). Found across avocado-growing regions of coastal Australia including the Mid North Coast. Feeds in the rosette of young leaves surrounding developing fruit.
Season: Spring
Natural remedies: Neem Oil Spray
Bacterial Canker (Tomato)
Disease — Affects: Tomato
Wilting of leaflets starting at the margins and working inward. Yellow-brown streaking inside stems when cut. White bird's-eye spots on fruit — small white circles each with a dark brown centre.
Cause: Clavibacter michiganensis subsp. michiganensis. Bacterial disease spread on seed, transplants, and by handling plants. Found across all tomato-growing regions of Australia.
Season: Spring, Summer
Natural remedies: Copper Spray (Copper Oxychloride)
Bacterial Spot (Tomato)
Disease — Affects: Tomato, Capsicum
Small dark water-soaked spots on leaves, stems, and fruit. Leaf spots develop a yellow halo and the centre may fall out, giving a shot-hole appearance. Fruit shows raised, rough, wart-like spots.
Cause: Xanthomonas species. Bacterial disease spread by water splash, seeds, and handling. Found across all tomato and capsicum growing regions of Australia.
Season: Spring, Summer
Natural remedies: Copper Spray (Copper Oxychloride)
Bacterial Wilt
Disease — Affects: Tomato, Capsicum, Eggplant, Potato, Cucumber
Sudden wilting of the entire plant or individual branches, often without obvious yellowing or spotting. Plant may look healthy in the morning and collapsed by afternoon. Does not recover when watered.
Cause: Ralstonia solanacearum. A soil-borne bacterium spread by water, contaminated tools, and infected soil. Present across tropical and subtropical Australia. More common in northern NSW and Queensland, but present on the Mid North Coast in warm, moist conditions.
Season: Spring, Summer
There is no cure. Remove and dispose of infected plants without composting. Don't plant solanums in the same spot for at least 3 years.
Bandicoots
Pest — Affects: Root vegetables, Bulbs, Seedlings, Lawn and garden beds
Conical holes dug in garden beds and lawn overnight — bandicoots dig with their front feet, leaving characteristic pointed excavations 5–10cm deep. Seedlings and bulbs may be dug up entirely.
Cause: Long-nosed Bandicoot (Perameles nasuta) and Southern Brown Bandicoot. Native protected species. Common in coastal NSW and the Mid North Coast where bush adjoins gardens.
Season: Spring, Summer, Autumn, Winter
They're after beetle larvae and earthworms mostly, so they're actually doing something useful. The hole-digging is annoying but they're native and protected. Low fencing around vulnerable beds is the practical answer.
Bean Fly
Pest — Affects: Beans, Soybean, Cowpea
Seedlings and young plants wilt and collapse. Close inspection of the stem base reveals tunnelling and the presence of white maggots inside. Reddish-brown staining of stem tissue at soil level.
Cause: Bean Fly (Ophiomyia phaseoli). A significant pest in tropical and subtropical Australia. Found across coastal and inland Queensland, northern NSW, and the NT. A real problem on the Mid North Coast, particularly in the warmer months.
Season: Spring, Summer
Natural remedies: Neem Oil Spray
Bean fly destroyed my first summer bean crop. Planting in autumn gives better results on the Mid North Coast — beans planted in March–April largely avoid the worst bean fly pressure.
Black Spot (Rose)
Disease — Affects: Rose
Circular black spots with fringed or feathery edges on upper leaf surfaces. Yellow halo around spots. Infected leaves drop, leaving the plant defoliated. Repeated defoliation weakens the plant.
Cause: Diplocarpon rosae. Fungal disease spread by water splash. Found across all of Australia. Worse in humid coastal regions.
Season: Spring, Summer, Autumn
Natural remedies: Copper Spray (Copper Oxychloride)
Blossom Drop (Capsicum)
Environmental — Affects: Capsicum, Chilli
Flowers fall off before setting fruit. Plant looks healthy and flowers freely but carries no fruit. Can be caused by temperature extremes or water stress at pollination.
Cause: Temperature extremes, low humidity, or water stress during pollination. Capsicums are more sensitive to temperature than tomatoes — they stop setting fruit more readily in heat or cold.
Season: Summer, Winter
Blossom End Rot
Environmental — Affects: Tomato, Capsicum, Zucchini, Watermelon, Cucumber
Dark brown to black leathery patch at the blossom end (the bottom) of the fruit. Starts small and expands. Affected area becomes sunken and dry. The rest of the fruit is often unaffected.
Cause: Calcium deficiency in the developing fruit — but usually not a calcium deficiency in the soil. The cause is irregular watering that prevents consistent calcium uptake. Very common on the Mid North Coast and across coastal Australia.
Season: Spring, Summer
I had this badly on my first season of tomatoes. Consistent watering — not just watering more, but watering regularly — fixed it. A calcium foliar spray helps but consistent moisture is the real solution.
Bolting
Environmental — Affects: Lettuce, Spinach, Coriander, Brassicas, Fennel, Silverbeet, Basil
Plant sends up a tall flowering stem rapidly, leaves become bitter and small, and the plant's eating quality deteriorates quickly. Once bolted, the plant cannot be reversed.
Cause: A natural reproductive response to environmental stress — usually heat, lengthening days, or drought. Different crops have different bolt triggers. Found across all of Australia — on the Mid North Coast, heat and long summer days trigger bolting from late spring.
Season: Spring, Summer
The solution is timing. Cool-season crops need to be in and harvested before the heat hits. On the Mid North Coast, lettuce planted in February–March can run before the real heat does.
Broad Bean Chocolate Spot
Disease — Affects: Broad Beans
Chocolate-brown spots on all above-ground parts of the plant — leaves, stems, and pods. In severe cases, spots merge and plants may die. Often worse in a wet season.
Cause: Botrytis fabae. Fungal disease specific to broad beans. Found across broad bean growing regions of Australia. Worse in cool, wet, humid conditions.
Season: Winter, Spring
Natural remedies: Copper Spray (Copper Oxychloride)
Brown Rot (Stonefruit)
Disease — Affects: Peach, Nectarine, Plum, Cherry, Apricot
Rapid brown rotting of ripe and ripening fruit, often starting at a wound or crack. Rings of pale fungal spore masses form on the rotted surface. Fruit may mummify on the tree. Flowers and young shoots can also be infected.
Cause: Monilinia fructicola. Found across all stone fruit growing regions of Australia. Particularly severe in warm humid conditions around harvest time.
Season: Spring, Summer
Natural remedies: Copper Spray (Copper Oxychloride)
Cabbage White Butterfly
Pest — Affects: Cabbage, Broccoli, Cauliflower, Kale, Brussels Sprouts, Bok Choy, Rocket
Irregular holes chewed through leaves, often leaving the mid-rib and larger veins intact. Heavy infestations can strip a plant to a skeleton within days. Look for pale green caterpillars resting on the underside of leaves, and small yellow-white eggs on leaf undersides.
Cause: Larvae of the Cabbage White Butterfly (Pieris rapae). Adults are the familiar small white butterflies with black wingtip spots seen fluttering around brassicas. Introduced species, now found across all of Australia.
Season: Spring, Autumn, Winter
Natural remedies: Bt Spray (Bacillus thuringiensis), Chilli and Garlic Spray, Neem Oil Spray
This was our first major pest problem on the brassicas. The caterpillars are hard to see until the damage is obvious. Bt spray was the thing that actually worked.
Carrot Rust Fly
Pest — Affects: Carrot, Parsnip, Celery, Parsley
Yellow-bronze tunnelling and rusty marks on carrot skin. Fine tunnels running through the root. Attacked carrots often rot and become inedible. Foliage may yellow.
Cause: Carrot Fly (Psila rosae). Present in cooler regions of Australia, particularly Victoria, Tasmania, and the cooler parts of NSW. Less common in subtropical coastal areas.
Season: Spring, Autumn
Natural remedies: Diatomaceous Earth
Catface (Tomato Fruit Deformity)
Environmental — Affects: Tomato
Severely deformed fruit with puckered skin, scarring, and irregular lobes at the blossom end. Interior shows corky brown tissue and missing sections. Occurs on the first fruits of the season.
Cause: Disruption to normal flower development during cold or extreme weather at fruit set. Not a pest or pathogen — purely environmental. Common on large-fruited beefsteak varieties.
Season: Spring
Citrus Gall Wasp
Pest — Affects: Lemon, Lime, Orange, Grapefruit, Mandarin
Swollen, knobbly galls on the branches and twigs of citrus trees. Branches may die back beyond the gall. Reduces vigour and fruit production over time. Galls are most visible in autumn and winter when they have fully formed.
Cause: Citrus Gall Wasp (Bruchophagus fellis). Native Australian insect, but a serious introduced pest in citrus. Worst in coastal Queensland and NSW. A real problem on the Mid North Coast.
Season: Spring
Prune out galls before October to remove larvae before adults emerge. Cut at least 10cm below the gall. Destroy removed material — don't compost it. Consistent annual pruning keeps it manageable.
Citrus Leafminer
Pest — Affects: Lemon, Lime, Orange, Mandarin, Grapefruit
Silvery winding tunnels on new citrus leaves. Affected leaves curl and distort. Mostly affects young trees and the spring/summer flush of new growth. Established trees tolerate it well.
Cause: Citrus Leafminer (Phyllocnistis citrella). Introduced pest now found across all citrus-growing regions of Australia. Particularly prevalent in warm coastal areas including the Mid North Coast.
Season: Spring, Summer
Natural remedies: Neem Oil Spray
Healthy established trees can handle leafminer without treatment. I spray neem oil on new flushes on my younger trees.
Club Root
Disease — Affects: Cabbage, Broccoli, Cauliflower, Turnip, Radish, Kale, Bok Choy
Stunted growth, yellowing, wilting during the day with partial recovery at night. Roots form large distorted club-shaped galls. Once present in soil, it persists for up to 20 years.
Cause: Plasmodiophora brassicae. A soil-borne pathogen. Present across all brassica-growing regions of Australia. Can be introduced on contaminated transplants, soil, or equipment.
Season: Autumn, Winter, Spring
If you have club root, lime heavily to raise pH above 7 and don't plant brassicas in that bed for several years. Introducing club root on purchased transplants is a real risk — always inspect roots before planting.
Codling Moth
Pest — Affects: Apple, Pear, Quince, Walnut
Entry holes in fruit surrounded by brown frass. Tunnels through the flesh of apple and pear, usually heading directly to the core. Fruit may drop early. Larvae found in harvested fruit.
Cause: Codling Moth (Cydia pomonella). Introduced pest, now widespread across all apple-growing regions of Australia. A significant challenge for home orchardists.
Season: Spring, Summer
Natural remedies: Neem Oil Spray
Collar Rot (Phytophthora)
Disease — Affects: Tomato, Capsicum, Avocado, Citrus, Macadamia
Dark discolouration and decay at the stem base at or just below soil level. Bark or outer tissue may be soft and water-soaked. Plants wilt and die rapidly, especially in warm wet conditions.
Cause: Phytophthora cinnamomi and related species. Found across all of Australia — particularly devastating in avocado and native vegetation but also affects vegetables in warm, wet, poorly drained soils.
Season: Summer
Natural remedies: Worm Castings Soil Drench
Corn Earworm (Helicoverpa)
Pest — Affects: Corn, Tomato, Capsicum, Beans, Cotton
Caterpillars feed inside the corn ear, entering at the silk end. Damaged silks, frass (droppings), and the caterpillar itself found inside the husk. On tomatoes, round entry holes in fruit with frass around them.
Cause: Helicoverpa armigera (Cotton Bollworm) and H. punctigera. One of Australia's most damaging insect pests, found across all states. A significant pest across the Mid North Coast and all of coastal NSW.
Season: Spring, Summer, Autumn
Natural remedies: Bt Spray (Bacillus thuringiensis), Neem Oil Spray
Corn Smut
Disease — Affects: Corn
Large, swollen, silvery-grey galls on cobs, silks, tassels, and occasionally leaves. The galls rupture to release masses of sooty black spores. Infected cobs produce no grain.
Cause: Ustilago maydis. A fungal smut disease. Found across corn-growing regions of Australia. Spores persist in soil for years.
Season: Summer
Cracking and Splitting (Tomato)
Environmental — Affects: Tomato
Radial or concentric cracks on ripening fruit. Can be shallow or deep. Deep cracks allow entry of pathogens and insects. Mostly affects fruit that has been under water stress and then receives a sudden large amount of water.
Cause: Sudden change in water availability after a dry period. The fruit absorbs water rapidly and the skin can't expand fast enough. Irregular rainfall combined with irrigation is a common cause.
Season: Summer
Crown Rot (Sclerotinia)
Disease — Affects: Lettuce, Carrot, Beans, Celery, Sunflower, Tomato, Zucchini
White fluffy mould at the base of the stem or on the crown of the plant. Tissue beneath the mould turns soft and brown. Hard black structures (sclerotia) form inside the stem. Plant wilts and collapses.
Cause: Sclerotinia sclerotiorum. Soil-borne fungus with a very wide host range. Found across southern and eastern Australia. The sclerotia survive in soil for 3–5 years making rotation essential.
Season: Autumn, Winter, Spring
Natural remedies: Worm Castings Soil Drench
Crusader Bug
Pest — Affects: Tomato, Capsicum, Beans, Macadamia, Native plants
Yellowing and distortion around feeding sites on young growth. Fruit may be marked or scarred at feeding points.
Cause: Crusader Bug (Mictis profana). Native Australian insect. Found across eastern Australia including the Mid North Coast. Generally a minor pest.
Season: Summer, Autumn
Natural remedies: Soap Spray
Cucumber Mosaic Virus
Disease — Affects: Cucumber, Zucchini, Pumpkin, Tomato, Capsicum, Beans, Basil
Mosaic pattern of light and dark green on leaves, leaf distortion and narrowing. Cucumber fruit may have light and dark green mottled streaks. Plant growth is stunted. No cure.
Cause: Cucumber Mosaic Virus (CMV), spread by aphids. One of the most widespread plant viruses globally. Found across all of Australia. Aphid control is the key prevention strategy.
Season: Spring, Summer, Autumn
Natural remedies: Neem Oil Spray, Soap Spray
Cutworms
Pest — Affects: Tomato, Capsicum, Lettuce, Cabbage, Corn, Beans, Seedlings
Seedlings and young plants cut off cleanly at or just below soil level overnight. Plants appear healthy one day and are found lying on the soil the next. No visible pest on the plant — search in the top few centimetres of soil around the base.
Cause: Larvae of several moth species in the family Noctuidae. Found across all of Australia. Most common at site preparation time when newly turned soil exposes pupae.
Season: Spring, Summer, Autumn
Natural remedies: Bt Spray (Bacillus thuringiensis), Diatomaceous Earth
Damping Off
Disease — Affects: All seedlings
Seedlings collapse at or near soil level, the stem becoming pinched and water-soaked at the base. Can affect seedlings before or after emergence. Can wipe out an entire tray of seedlings rapidly.
Cause: Pythium, Rhizoctonia, and Fusarium species, often acting together. Favoured by overwatering and poor air circulation. Common in potting mix that stays wet for extended periods.
Season: Spring, Summer
Natural remedies: Worm Castings Soil Drench
I've lost whole trays of tomato seedlings to this. The fix was simple: water less, improve drainage, and use fresh potting mix each season.
Diamondback Moth
Pest — Affects: Cabbage, Broccoli, Kale, Cauliflower, Bok Choy, Mustard Greens
Window-pane feeding damage — upper leaf skin eaten but lower skin left intact, creating translucent patches. Tiny pale green caterpillars wriggle vigorously and drop on a thread when disturbed.
Cause: Diamondback Moth (Plutella xylostella). One of the most damaging brassica pests in Australia. Found in all states. Notorious for developing resistance to synthetic insecticides.
Season: Spring, Summer, Autumn, Winter
Natural remedies: Bt Spray (Bacillus thuringiensis), Neem Oil Spray
Downy Mildew
Disease — Affects: Lettuce, Spinach, Cucumber, Basil, Grapes, Brassicas
Yellow or pale green patches on the upper surface of leaves, with grey-purple furry growth on the corresponding underside. Affected tissue dies and turns brown. Plants may collapse in severe cases.
Cause: Water mould pathogens (Peronospora and related species). Not a true fungus. Found across all of Australia. Particularly problematic in humid coastal regions including the NSW Mid North Coast.
Season: Autumn, Winter, Spring
Natural remedies: Copper Spray (Copper Oxychloride)
Downy Mildew — Basil
Disease — Affects: Basil
Yellowing between veins on upper leaf surfaces, with grey-purple downy growth on the underside of affected areas. Leaves drop rapidly. Plant can collapse within days in warm humid conditions.
Cause: Peronospora belbahrii. Basil-specific downy mildew. Relatively recent arrival in Australia. Spreads via spores on wind and water. A real problem in humid coastal areas including the Mid North Coast.
Season: Summer, Autumn
Natural remedies: Copper Spray (Copper Oxychloride)
I've had this wipe out an entire basil planting in under a week. The trick is planting with wide spacing for airflow and avoiding overhead watering. Once it's there, it moves fast.
Downy Mildew — Onion
Disease — Affects: Onion, Leek, Garlic, Shallot
Pale green to yellow patches on leaves, with greyish-purple downy growth on the surface. Leaves collapse and die from the tips. Bulb development is reduced.
Cause: Peronospora destructor. Found across all onion-growing regions of Australia. Worse in cool, humid conditions.
Season: Autumn, Winter, Spring
Natural remedies: Copper Spray (Copper Oxychloride)
Early Blight (Alternaria)
Disease — Affects: Tomato, Potato, Capsicum, Eggplant
Dark brown to black spots on older leaves, with characteristic concentric rings (target-board pattern) and a yellow halo. Starts on lower leaves and moves up the plant. Affected leaves yellow and drop.
Cause: Alternaria solani and related species. Fungal pathogen found across all of Australia. Common on the Mid North Coast in warm humid weather.
Season: Spring, Summer, Autumn
Natural remedies: Copper Spray (Copper Oxychloride)
Earwigs
Pest — Affects: Lettuce, Seedlings, Strawberry, Corn, Stone fruit
Ragged holes in leaves and fruit, particularly towards leaf edges. Damage occurs at night. Earwigs are actually beneficial predators of aphids and other insects, so damage must be weighed against their positive role.
Cause: European Earwig (Forficula auricularia, introduced) and native earwig species. Found across Australia in moist garden environments.
Season: Spring, Summer, Autumn
Natural remedies: Diatomaceous Earth
Eggfruit Caterpillar (Leucinodes)
Pest — Affects: Eggplant
Wilting shoot tips that turn yellow and die. Holes bored into fruit with frass. Infested fruit rots from the inside. A serious pest that can make eggplant production very difficult without management.
Cause: Eggfruit Borer (Leucinodes orbonalis). A major pest of eggplant across tropical and subtropical Australia. Found in coastal Queensland and northern NSW — present on the Mid North Coast.
Season: Spring, Summer
Natural remedies: Bt Spray (Bacillus thuringiensis), Neem Oil Spray
Fig Moth Borer
Pest — Affects: Fig
Frass (sawdust-like droppings) at the eye of the fig, sometimes with webbing. Developing figs rot from inside. Ripe figs may be tunnelled. Can significantly reduce yield.
Cause: Fig Moth (Ephestia cautella) and related species. Found across fig-growing regions of Australia. More common in warm coastal areas.
Season: Summer, Autumn
Natural remedies: Neem Oil Spray
Flea Beetles
Pest — Affects: Brassicas, Tomato, Eggplant, Potato, Radish, Lettuce
Numerous tiny round holes in leaves — as if the plant has been hit with fine buckshot. Worst on seedlings and young plants. The beetles are tiny, jump rapidly when disturbed.
Cause: Multiple flea beetle species (Altica and Phyllotreta species). Found across Australia. More problematic in drier inland areas but present in coastal NSW.
Season: Spring, Summer
Natural remedies: Diatomaceous Earth, Neem Oil Spray
Frost Damage
Environmental — Affects: Tomato, Capsicum, Basil, Eggplant, Cucumber, Beans, Sweet Potato
Water-soaked, translucent appearance on leaves and stems after a cold night. As leaves warm in the morning sun, they become black and mushy. Tender new growth is affected first. Plants may recover partially from light frost.
Cause: Ice crystal formation in plant cells below 0°C ruptures cell walls. Most common in the Southern Tablelands, Victorian Alps, Tasmania, and alpine regions of NSW. Less common on the Mid North Coast but light frosts can occur on clear winter nights in sheltered valleys.
Season: Winter
On the Mid North Coast we rarely get frosts but it pays to be cautious with frost-sensitive plants from June to August. Cold air pools in the valley floor — higher ground stays warmer.
Fruit Fly (Queensland and Mediterranean)
Pest — Affects: Tomato, Capsicum, Mango, Stonefruit, Citrus, Guava, Feijoa, Pumpkin
Soft dimpled areas on fruit skin. Maggots inside fruit. Premature fruit drop. Stinging puncture marks from female laying eggs. Infested fruit quickly rots from the inside.
Cause: Queensland Fruit Fly (Bactrocera tryoni) is the primary species in eastern Australia and a serious pest on the Mid North Coast. Mediterranean Fruit Fly (Ceratitis capitata) is the main species in WA. QFF is widespread across coastal and inland NSW.
Season: Spring, Summer, Autumn
Natural remedies: Neem Oil Spray
Fruit fly is a serious problem on the Mid North Coast. We use exclusion netting on tomatoes and capsicums. Protein bait traps help with monitoring. Nothing organic fully solves it once the population is established — prevention and exclusion are the best approach.
Fungus Gnats
Pest — Affects: Seedlings, Lettuce, Herbs, Tomato seedlings, Most plants in seedling stage
Tiny dark flies hovering around soil and plants. Seedlings damping off or wilting for no apparent reason — larvae feed on fine root hairs and can introduce pathogens. Most damaging to seedlings and cuttings in pots.
Cause: Fungus Gnat species (Bradysia spp. and related). Widespread across Australia. A particular problem in seedling trays and pots with consistently moist potting mix.
Season: Spring, Summer, Autumn, Winter
Natural remedies: Neem Oil Spray, Garlic Spray
Fusarium Wilt
Disease — Affects: Tomato, Capsicum, Basil, Watermelon, Banana, Beans
Yellowing that begins on one side of the plant or on lower leaves. Wilting that doesn't recover with watering. Brown discolouration of the vascular tissue visible when the stem is cut. Plant eventually dies.
Cause: Fusarium oxysporum. A soil-borne fungal pathogen with host-specific strains. Persistent in soil for years. Found across all of Australia. Worst in warm soil temperatures above 24°C — a regular problem in the warmer months on the Mid North Coast.
Season: Spring, Summer
Natural remedies: Worm Castings Soil Drench
Grasshoppers and Locusts
Pest — Affects: Corn, Beans, Lettuce, Cabbage, Capsicum, Tomato, Sweet Potato, Most vegetables
Large irregular sections of leaves eaten or entirely consumed. Can defoliate a plant rapidly. Unlike caterpillars, grasshoppers feed during the day and can be seen. Damage often appears suddenly and spreads quickly in outbreak years.
Cause: Multiple species including Wingless Grasshopper (Phaulacridium vittatum) and Migratory Locust (Locusta migratoria). Found across Australia, worst in inland and rural areas. On the Mid North Coast, grasshopper pressure increases in dry years and after heatwaves.
Season: Spring, Summer
Natural remedies: Chilli and Garlic Spray, Neem Oil Spray
Grey Mould (Botrytis)
Disease — Affects: Tomato, Strawberry, Lettuce, Beans, Grapes, Zucchini
Grey fuzzy mould on flowers, fruit, and dying or damaged tissue. Infected tissue rots quickly. Strawberry fruit becomes covered in grey spores. Tomatoes may develop ghost spot — faint ring marks on green fruit.
Cause: Botrytis cinerea. Found across all of Australia. Particularly problematic in cool humid conditions with poor air circulation.
Season: Autumn, Winter, Spring
Natural remedies: Copper Spray (Copper Oxychloride)
Harlequin Bug
Pest — Affects: Cabbage, Broccoli, Cauliflower, Kale, Brussels Sprouts, Turnip, Radish
Wilting, yellowing, and browning of leaves from feeding punctures. Plants may collapse in heavy infestations. The bugs are easy to spot — they're large, colourful, and don't hide.
Cause: Harlequin Bug (Dindymus versicolor). A native Australian insect found across south-eastern and eastern Australia, including coastal NSW. A significant brassica pest on the Mid North Coast.
Season: Spring, Summer, Autumn
Natural remedies: Neem Oil Spray, Soap Spray, Chilli and Garlic Spray
Heat Stress
Environmental — Affects: Tomato, Lettuce, Spinach, Beans, Peas, Herbs
Wilting during the heat of the day (recovering at night), flower drop without fruit set, scorched leaf margins, bleached patches on leaves exposed to afternoon sun. Tomatoes fail to set fruit above 35°C.
Cause: High temperatures exceeding the plant's tolerance range. A common summer issue across all of Australia, including the Mid North Coast where temperatures regularly exceed 35°C.
Season: Summer
Shade cloth over tomatoes during heatwaves has made a real difference. The plants that were shaded still set fruit through the hot spell, the unprotected ones didn't.
Ink Disease (Iris)
Disease — Affects: Bulbous Iris, Freesia, Sparaxis
Black ink-like marks on bulb scales. Rotting of outer bulb tissue. Poor emergence and stunted growth from infected bulbs.
Cause: Drechslera iridis and related fungi. Found across bulb-growing regions of Australia.
Season: Autumn, Winter
Late Blight
Disease — Affects: Tomato, Potato
Large irregular water-soaked lesions on leaves that quickly turn brown-black. White fluffy growth on the underside of lesions in humid conditions. Can destroy an entire planting within days. Infected fruit develop firm brown rot.
Cause: Phytophthora infestans. The same pathogen responsible for the Irish Potato Famine. Found across all of Australia in suitable conditions. More common in cooler, wetter regions but can occur on the Mid North Coast in cool wet periods.
Season: Autumn, Winter, Spring
Natural remedies: Copper Spray (Copper Oxychloride)
Leaf Curl (Peach Leaf Curl)
Disease — Affects: Peach, Nectarine, Apricot
Leaves emerge puckered, curled, and thickened in spring. Affected leaves are red or pink initially, later turning yellow-grey as spores are released. Severe infections cause defoliation, weakening the tree.
Cause: Taphrina deformans. Fungal disease that infects during cool wet periods when buds are breaking in spring. Found across all stone fruit growing regions of Australia. Worst in cool, wet spring conditions.
Season: Spring
Natural remedies: Copper Spray (Copper Oxychloride)
Leaf Miners
Pest — Affects: Tomato, Beans, Capsicum, Silverbeet, Brassicas
Winding white or pale green trails visible through the leaf, forming irregular serpentine patterns. The trails grow wider as the larva grows. Affected leaves may yellow around heavily mined areas.
Cause: Various leafminer fly species (Liriomyza spp. and related). Found across all of Australia. Cosmetically unpleasant but rarely fatal to established plants.
Season: Spring, Summer
Natural remedies: Neem Oil Spray
Leek Moth
Pest — Affects: Leek, Onion, Garlic, Chive
Longitudinal tunnels in leek leaves and inside the shaft. Leaves wilt and die back from the tip. Frass visible inside the tunnels when leaf is split open.
Cause: Acrolepiopsis assectella. Pest of alliums. Found mainly in cooler regions of south-eastern Australia.
Season: Spring, Autumn
Natural remedies: Bt Spray (Bacillus thuringiensis)
Light Brown Apple Moth
Pest — Affects: Apple, Pear, Grape, Citrus, Berry fruit, Many ornamentals
Leaves webbed together or rolled around a feeding larva. Fruit scarred or tunnelled at skin level. Damage is widespread but usually not as severe as Codling Moth.
Cause: Light Brown Apple Moth (Epiphyas postvittana). Native Australian leafroller moth with a very wide host range. Found across southern and eastern Australia.
Season: Spring, Summer, Autumn
Natural remedies: Bt Spray (Bacillus thuringiensis), Neem Oil Spray
Lily Caterpillar
Pest — Affects: Agapanthus, Clivia, Hippeastrum, Spider Lily, Lily
Leaves stripped to bare stems overnight. Entire plants can be defoliated very rapidly. The caterpillars are distinctive and numerous.
Cause: Lily Caterpillar (Spodoptera picta). Found across tropical and subtropical Australia. Common in coastal NSW and a recurring problem in ornamental gardens on the Mid North Coast.
Season: Spring, Summer
Natural remedies: Bt Spray (Bacillus thuringiensis), Chilli and Garlic Spray
Loopers (Cabbage Looper)
Pest — Affects: Cabbage, Broccoli, Cauliflower, Lettuce, Spinach, Silverbeet, Tomato
Irregular holes in leaves, often more ragged than Cabbage White Butterfly damage. The caterpillar's looping movement is distinctive. Usually less destructive than hornworms but can build up in numbers.
Cause: Cabbage Looper (Chrysodeixis eriosoma) and related species. Found across coastal and subtropical Australia. Common on the Mid North Coast.
Season: Spring, Summer, Autumn
Natural remedies: Bt Spray (Bacillus thuringiensis), Neem Oil Spray
Mango Seed Weevil
Pest — Affects: Mango
No external symptom on fruit. The weevil lives inside the mango seed and only becomes apparent when the seed is cut open after harvest. Does not affect fruit quality.
Cause: Mango Seed Weevil (Sternochetus mangiferae). Present in Queensland and northern NSW. A quarantine pest that restricts the movement of mango fruit interstate from affected areas.
Season: Spring, Summer
Mealybugs
Pest — Affects: Capsicum, Eggplant, Tomato, Citrus, Passionfruit, Potato
White cottony or waxy masses in leaf axils, on stems, and at the base of plants. Sticky honeydew residue and sooty mould. Yellowing, stunting, and wilting of affected growth.
Cause: Multiple species including Longtailed Mealybug (Pseudococcus longispinus) and Citrus Mealybug (Planococcus citri). Found across all of Australia.
Season: Spring, Summer, Autumn
Natural remedies: Neem Oil Spray, Soap Spray
Millipedes
Pest — Affects: Strawberry, Seedlings, Ripening fruit touching soil, Root vegetables
Surface feeding on ripening strawberries and fruit touching the soil. Holes in ripe fruit. Generally decomposers, but can damage soft plant material when populations are high.
Cause: Portuguese Millipede (Ommatoiulus moreletii, introduced) and various native species. Found across southern and eastern Australia. Portuguese Millipede is a particular pest in SA and WA but spreading.
Season: Autumn, Spring
Natural remedies: Diatomaceous Earth
Mites — Broad Mite
Pest — Affects: Capsicum, Eggplant, Cucumber, Beans, Begonia
New growth is stunted, distorted, and often turns bronze or rusty brown. Leaves cup downward and become thick and leathery. Growing tips may die. Damage is sometimes confused with herbicide damage or virus.
Cause: Broad Mite (Polyphagotarsonemus latus). Microscopic — requires a hand lens or microscope to see. Found across tropical and subtropical Australia. Present on the Mid North Coast in warm conditions.
Season: Spring, Summer
Natural remedies: Neem Oil Spray, Soap Spray
Neck Rot (Onion)
Disease — Affects: Onion, Garlic
Soft, water-soaked rot at the neck (top) of the bulb, usually developing in storage. Grey fungal growth may be visible. Rotted tissue turns brown and eventually dries to a papery mummified state.
Cause: Botrytis allii and related species. Found across onion-growing regions of Australia. Spreads in humid conditions before and after harvest.
Season: Autumn
Let onions dry down fully in the ground before harvest. Cure them properly in a dry airy spot for 2–3 weeks before storage. Rushing this step leads to neck rot in storage.
Nutrient Deficiency — Iron Chlorosis
Environmental — Affects: Tomato, Citrus, Beans, Blueberry, Garlic, Roses
Yellowing between the leaf veins on young leaves while the veins themselves stay green. Older leaves may remain healthy while new growth is pale yellow. Severe cases cause entire new leaves to be pale yellow or white.
Cause: Iron unavailable to the plant, usually due to high soil pH rather than an actual lack of iron in the soil. Most Australian soils have adequate iron. Common in alkaline soils or where lime has been over-applied.
Season: Spring, Summer
Natural remedies: Worm Castings Soil Drench
Nutrient Deficiency — Magnesium
Environmental — Affects: Tomato, Capsicum, Potato, Citrus, Beans
Interveinal yellowing on older leaves, similar to iron deficiency but affecting older growth first rather than new growth. Leaves may curl upward. Tomatoes often show this towards the end of a long season.
Cause: Magnesium deficiency in the soil or impaired uptake. Can be induced by excess potassium or calcium competing with magnesium uptake. Fairly common in heavily cropped gardens.
Season: Summer, Autumn
A dilute Epsom salt foliar spray (magnesium sulphate, 1 tbsp per litre) is a fast fix. Not a substitute for improving soil organic matter long-term.
Nutrient Deficiency — Nitrogen
Environmental — Affects: Corn, Tomato, Lettuce, Brassicas, Beans, Zucchini
General yellowing starting on older lower leaves, moving upwards as the deficiency worsens. Growth is slow and stunted. Plants look pale and lack vigour. Corn shows a characteristic V-shaped yellowing from the leaf tip.
Cause: Insufficient available nitrogen in the soil, or nitrogen leached from the soil by heavy rain. Common in sandy soils and in gardens with limited organic matter input.
Season: Spring, Summer
Natural remedies: Worm Castings Soil Drench
Nutrient Deficiency — Phosphorus
Environmental — Affects: Tomato, Corn, Beans, Brassicas
Purple or reddish discolouration of leaf undersides and stems, particularly in young plants. Growth is slow and root development is poor. Symptoms are most obvious in cool weather or when soil is cold.
Cause: Phosphorus deficiency or unavailability — often due to cold soil rather than actual lack of phosphorus. Cold soil prevents root uptake. Acidic or very alkaline soils can also lock out phosphorus.
Season: Winter, Spring
Natural remedies: Worm Castings Soil Drench
Nutrient Deficiency — Potassium
Environmental — Affects: Tomato, Potato, Beans, Corn, Citrus
Leaf margins and tips turn brown and dry, starting on older leaves. The brown edge is distinct from the still-green centre. Fruit on tomatoes may ripen unevenly, with green or yellow patches remaining.
Cause: Potassium deficiency in the soil. Sandy soils are most prone. Can also be induced by excess calcium or magnesium locking out potassium uptake.
Season: Spring, Summer
Natural remedies: Worm Castings Soil Drench
Onion White Rot
Disease — Affects: Onion, Garlic, Leek, Shallot, Chive
Yellowing and dying back of foliage. White fluffy fungal growth at the base of the bulb. Bulb rots from the base upward. Small black sclerotia (like poppy seeds) on the outer papery scales.
Cause: Sclerotium cepivorum. Soil-borne fungal pathogen that persists in soil for 20+ years. Found across all allium-growing regions of Australia. Introduced on infected planting material or soil.
Season: Autumn, Winter, Spring
There is no cure once established. Strict hygiene with allium planting material is essential — don't use homesaved garlic or onion sets from an unknown source.
Passionfruit Woodiness Virus
Disease — Affects: Passionfruit
Leaves mottled yellow and green, distorted and smaller than normal. Fruit is small, hard, and woody with little pulp. Production declines dramatically. No cure — remove and replace.
Cause: Passionfruit Woodiness Virus (PWV), spread by aphids. Found across Queensland, NSW, and other passionfruit-growing regions. The Mid North Coast has good passionfruit-growing conditions but virus pressure is significant.
Season: Spring, Summer, Autumn
Natural remedies: Neem Oil Spray, Soap Spray
Controlling aphids is the primary prevention strategy. Once the vine has woodiness virus, it needs to come out. Start fresh with a new vine from a reputable nursery on clean rootstock.
Pear and Cherry Slug
Pest — Affects: Pear, Cherry, Quince, Plum
Upper surface of leaves is skeletonised, leaving only the veins. The slime-covered larvae are easily visible on the upper leaf surface. Severe infestations give trees a scorched, brown appearance.
Cause: Cherry Slug Sawfly (Caliroa cerasi). Found across stone and pome fruit growing regions of Australia. A common pest in home orchards.
Season: Spring, Summer
Natural remedies: Diatomaceous Earth, Soap Spray
Phytophthora Dieback — Native Plants
Disease — Affects: Grevillea, Banksia, Hakea, Waratah, Macadamia
Sudden death of branches or entire plant. No visible pests. Roots are black and rotted. Yellowing and dieback progress from the tips inward. The plant appears to die of drought despite adequate moisture.
Cause: Phytophthora cinnamomi. Spread through soil movement, contaminated equipment, and water flow. Found across all of Australia — one of the most environmentally damaging plant pathogens in the country.
Season: Summer
Natural remedies: Worm Castings Soil Drench
Phytophthora Root Rot — Avocado
Disease — Affects: Avocado
Tip dieback, yellowing and browning of foliage. Canopy thinning. Roots are black and rotted. Fruit production declines. A major cause of avocado tree death in Australia.
Cause: Phytophthora cinnamomi. The same organism that drives Jarrah Dieback. Found across avocado-growing regions of Australia. Serious in subtropical coastal areas including the Mid North Coast.
Season: Summer, Autumn
Natural remedies: Worm Castings Soil Drench
Poor Fruit Set (Tomato)
Environmental — Affects: Tomato, Capsicum, Beans
Flowers open and fall off without setting fruit. Plant looks healthy and flowers abundantly but carries little to no fruit.
Cause: Temperature extremes during pollination. Tomatoes require temperatures between 13–35°C for successful pollen germination. Above 35°C or below 10°C, pollen fails. High humidity can also cause pollen to clump.
Season: Summer, Winter
I lost most of my January tomato crop to flower drop one summer. Shade cloth and consistent watering helped more the next year. Some varieties handle heat better — look for heat-tolerant varieties for summer planting.
Possums
Pest — Affects: Tomato, Corn, Beans, Leafy greens, Citrus, Stone fruit, Most vegetables
Large sections of plants stripped overnight. Fruit taken or partially eaten. Characteristic tearing damage rather than the clean cuts of caterpillars. Faeces left on or near plants.
Cause: Common Brushtail Possum (Trichosurus vulpecula) and Common Ringtail Possum (Pseudocheirus peregrinus). Native protected species found across eastern and southern Australia. A significant garden pest in rural and semi-rural areas of the Mid North Coast.
Season: Spring, Summer, Autumn, Winter
Natural remedies: Chilli and Garlic Spray
Possums are protected by law so trapping and relocating requires a permit. Physical exclusion netting is the only reliable long-term solution. Chilli spray has some deterrent effect but they get used to it.
Powdery Mildew
Disease — Affects: Zucchini, Cucumber, Pumpkin, Melon, Beans, Tomato, Peas, Roses
White to grey powdery coating on leaf surfaces, starting as small spots then spreading to cover entire leaves. Affected leaves yellow and die. Stems and fruit may also be affected in advanced cases.
Cause: Fungal pathogens in the order Erysiphales. Different species affect different plant families. Widespread across all of Australia. A near-universal problem with cucurbits in humid coastal environments like the Mid North Coast.
Season: Summer, Autumn
Natural remedies: Copper Spray (Copper Oxychloride)
Zucchinis almost always get powdery mildew late in the season on the Mid North Coast. I've accepted it as part of the plant's lifecycle. A copper spray early, when the first spots appear, can slow it down.
Pumpkin Beetle
Pest — Affects: Pumpkin, Zucchini, Cucumber, Melon
Round holes eaten in leaves and flowers. Seedlings may be destroyed entirely. Adults are easily seen feeding on foliage and flowers during the day.
Cause: Pumpkin Beetle (Aulacophora hilaris and related species). Found across coastal Queensland, northern NSW, and the NT. Present on the Mid North Coast but less severe than in tropical regions.
Season: Spring, Summer
Natural remedies: Neem Oil Spray, Chilli and Garlic Spray
Raspberry Cane Borer
Pest — Affects: Raspberry, Blackberry
Wilting and death of cane tips — the new growth wilts and collapses. A characteristic girdling ring or pair of puncture marks near the cane tip. Larvae tunnel down inside the cane.
Cause: Raspberry Cane Borer (Oberea bimaculata and related species). Found in cane fruit growing regions of south-eastern Australia.
Season: Spring, Summer
Root Knot Nematode
Pest — Affects: Tomato, Capsicum, Carrot, Beans, Lettuce, Most vegetables
Stunted, yellowing plants that wilt in warm conditions. Roots covered in small to large galls (swellings). The galls distinguish nematode damage from other root problems. Persistent across seasons as nematodes survive in soil.
Cause: Root Knot Nematodes (Meloidogyne species). Microscopic round worms in the soil. Found across all of Australia but most prevalent in warm, sandy soils — common in coastal NSW including the Mid North Coast.
Season: Spring, Summer
Natural remedies: Worm Castings Soil Drench
Root knot nematodes are a real challenge in warm coastal soils. Marigolds as a cover crop or interplanted are widely recommended as a suppressant. Raising organic matter helps.
Root Rot (Pythium)
Disease — Affects: Seedlings, Tomato, Capsicum, Beans, Zucchini, Most vegetables
Plants wilt despite adequate water, or fail to establish. Roots are brown, soft, and mushy rather than firm and white. Seedlings may damp off at the base. Plant decline is progressive.
Cause: Pythium spp. and related water moulds. Found across all of Australia. Common in the warm, moist soil of the Mid North Coast, particularly in heavy clay soils with poor drainage.
Season: Spring, Summer
Natural remedies: Worm Castings Soil Drench
Rust (Bean Rust)
Disease — Affects: Beans, Leek, Garlic
Rusty-orange pustules on the underside of leaves, with corresponding pale spots on the upper surface. Affected leaves yellow and die. Spreads rapidly in humid conditions.
Cause: Uromyces appendiculatus (Bean Rust) and related Puccinia species. Found across bean-growing regions of Australia. Worse in humid coastal areas.
Season: Summer, Autumn
Natural remedies: Copper Spray (Copper Oxychloride)
Scale Insects
Pest — Affects: Citrus, Fig, Stone fruit, Avocado, Rosemary, Bay, Passionfruit
Lumpy or crusty deposits on stems and leaves. Yellowing foliage, stunted growth. Sticky honeydew on leaves and stems, followed by sooty mould. Heavy infestations cause branch dieback.
Cause: Multiple scale species including Soft Brown Scale (Coccus hesperidum), White Wax Scale (Ceroplastes destructor), and various armoured scales. Widespread across Australia on woody plants.
Season: Spring, Summer
Natural remedies: Neem Oil Spray, Soap Spray
Septoria Leaf Spot
Disease — Affects: Tomato, Potato, Celery
Small circular spots with dark brown borders and lighter tan or grey centres on lower leaves. Tiny black dots may be visible in the centre of older spots. Leaves yellow and drop progressively up the plant.
Cause: Septoria lycopersici. Fungal disease spread by water splash. Found across all of Australia. Particularly common in humid coastal gardens during wet summers.
Season: Summer, Autumn
Natural remedies: Copper Spray (Copper Oxychloride)
Silverleaf Whitefly (SLWF)
Pest — Affects: Tomato, Capsicum, Cucumber, Beans, Sweet Potato, Pumpkin
Silvering of leaves on sweet potato and pumpkin — a toxic feeding reaction specific to this species. General plant yellowing, honeydew, sooty mould. Transmits Tomato Yellow Leaf Curl Virus.
Cause: Silverleaf Whitefly (Bemisia tabaci Biotype B). A serious invasive pest now established across subtropical and tropical Australia. A significant pest on the Mid North Coast in warmer months.
Season: Spring, Summer, Autumn
Natural remedies: Neem Oil Spray, Soap Spray
Slaters (Woodlice)
Pest — Affects: Seedlings, Strawberry, Lettuce, Ripening fruit touching soil
Irregular surface feeding on ripening fruit, seedling stems, and plant material touching the soil. Slaters are primarily decomposers and only become a pest problem when populations are very high or food sources are limited.
Cause: Common Slater (Porcellio scaber) and Pill Bug (Armadillidium vulgare), both introduced. Found across Australia in moist garden environments.
Season: Spring, Summer, Autumn, Winter
Natural remedies: Diatomaceous Earth
Slugs and Snails
Pest — Affects: Lettuce, Seedlings, Strawberry, Basil, Spinach, Silverbeet, Cabbage, Zucchini
Irregular ragged holes in leaves, especially around edges. Entire seedlings can be cut off at the base overnight. Silvery slime trails on leaves and soil surface are the key identifier.
Cause: Garden snails (Cornu aspersum, introduced) and various native and introduced slug species. Widespread across all of Australia, but particularly problematic in humid coastal regions like the NSW Mid North Coast where conditions rarely get dry enough to suppress populations naturally.
Season: Spring, Summer, Autumn, Winter
Natural remedies: Diatomaceous Earth
Worst around newly planted seedlings. I use diatomaceous earth around the base of plants when conditions are dry enough for it to work. On really wet nights, manual removal with a torch is faster.
Sooty Blotch and Flyspeck (Apple)
Disease — Affects: Apple, Pear
Dark sooty blotches or clusters of tiny black specks on apple and pear skin. Cosmetic damage only — does not affect eating quality. The blotches are on the surface and can sometimes be rubbed off.
Cause: Complex of fungal species. Found across apple-growing regions of Australia. More common in humid coastal and tablelands environments.
Season: Summer, Autumn
Natural remedies: Copper Spray (Copper Oxychloride)
Sooty Blotch on Capsicum
Disease — Affects: Capsicum, Chilli
Dark sooty patches on the fruit surface. Cosmetic only in most cases. Associated with humid conditions and poor air circulation.
Cause: Complex of saprophytic fungi growing on surface residues. Found across warm humid growing regions.
Season: Summer, Autumn
Natural remedies: Copper Spray (Copper Oxychloride)
Sooty Mould
Disease — Affects: Citrus, Tomato, Capsicum, Eggplant, Mango, Any plant with scale or aphids
Black powdery or sooty coating on leaves and stems. Not directly attacking the plant — grows on honeydew secreted by sap-sucking insects. Reduces photosynthesis by blocking light. Indicates an insect pest problem underneath.
Cause: Several fungal species that grow on honeydew secreted by aphids, scale, whitefly, and mealybugs. Found across all of Australia. Common wherever sap-sucking insects are present.
Season: Spring, Summer, Autumn
Natural remedies: Neem Oil Spray, Soap Spray
Fix the insect problem and the sooty mould will clear on its own over time. The mould itself is a symptom.
Sooty Mould — Mango
Disease — Affects: Mango
Heavy black coating on mango leaves and fruit. Associated with scale insect and mealybug populations feeding on the tree. Reduces fruit quality visually.
Cause: Saprophytic fungi growing on honeydew from mango scale and other sap-sucking pests. Found across mango-growing regions of Australia.
Season: Summer, Autumn
Natural remedies: Neem Oil Spray
Spider Mites
Pest — Affects: Tomato, Capsicum, Beans, Cucumber, Zucchini, Strawberry, Eggplant
Fine stippling or bronzing on leaves, starting on older growth and moving up the plant. Fine webbing on the undersides of leaves in heavy infestations. Leaves become dry, papery, and eventually drop.
Cause: Two-spotted Spider Mite (Tetranychus urticae) and Red-legged Earth Mite (Halotydeus destructor). Found across all of Australia. Spider mites thrive in hot, dry, dusty conditions and are significantly worse in extended dry spells.
Season: Spring, Summer
Natural remedies: Neem Oil Spray, Soap Spray
The trick is catching them early. By the time you see obvious bronzing and webbing the infestation is already heavy. I keep an eye on my tomatoes from November onwards.
Stink Bugs / Bronze Orange Bug
Pest — Affects: Citrus
Wilting shoot tips on citrus, especially on new spring growth. Young fruit may drop. Characteristic foul smell when bugs are disturbed. Heavy infestations can cause significant defoliation.
Cause: Bronze Orange Bug (Musgraveia sulciventris). A native Australian insect specific to citrus. Found across coastal Queensland, northern NSW, and the coastal Mid North Coast. Numbers fluctuate year to year.
Season: Spring, Summer
Natural remedies: Neem Oil Spray
Wear eye protection when removing these — they squirt a caustic liquid when disturbed. Knock them into soapy water using gloved hands or a stick. Neem spray on young nymphs is more effective than on adults.
Straw-coloured Fruit Fly (Lesser Pumpkin Fly)
Pest — Affects: Pumpkin, Zucchini, Cucumber, Melon
Premature yellowing and rotting of cucurbit fruit. Maggots inside affected fruit. Puncture marks on fruit surface where eggs were laid.
Cause: Lesser Pumpkin Fly (Zeugodacus cucumis). Found across tropical and subtropical Australia. A significant pest of cucurbits in coastal Queensland and northern NSW including the Mid North Coast.
Season: Spring, Summer, Autumn
Natural remedies: Neem Oil Spray
Sunscald
Environmental — Affects: Tomato, Capsicum, Eggplant, Cucumber
White or pale tan papery patches on fruit, usually on the side exposed to direct sun. Affected area becomes sunken and may develop secondary mould. Fruit quality is reduced but the rest may be edible.
Cause: Direct sun exposure on fruit that has been shaded by foliage and then exposed — often after removing leaves or after foliage loss from disease. Worst in summer heat on the Mid North Coast and across inland Australia.
Season: Summer
Termites
Pest — Affects: Corn, Sugar Cane, Woody plants, Timber structures adjacent to garden
Hollowed-out or collapsing stems on corn and similar crops. Mud tunnels on stems at soil level. Most termite damage in gardens is incidental — they are primarily a structural pest.
Cause: Multiple termite species (Family Termitidae). Found across all of Australia but particularly prevalent in tropical and subtropical areas including coastal NSW. The Mid North Coast has significant termite pressure.
Season: Spring, Summer
Termites in the vegetable garden are rarely a serious crop problem — they're more concerning near timber structures and the house. In the garden, keeping garden beds away from old timber is the main preventative.
Thrips
Pest — Affects: Onion, Leek, Capsicum, Tomato, Beans, Cucumber, Stone fruit
Silver or bronze streaking on leaves, often in a scratched or stippled pattern. Flowers may be distorted or drop early. Fruit can develop silvery scarring. Leaves may curl or distort on young growth.
Cause: Western Flower Thrips (Frankliniella occidentalis) and Onion Thrips (Thrips tabaci). Widespread across all of Australia. Also significant as vectors of Tomato Spotted Wilt Virus.
Season: Spring, Summer, Autumn
Natural remedies: Neem Oil Spray, Soap Spray
Tip Burn (Lettuce)
Environmental — Affects: Lettuce, Chinese Cabbage
Brown papery margins on inner leaves of lettuce hearts. Does not affect outer leaves. The damage is a calcium deficiency in developing inner leaves that cannot access calcium quickly enough during rapid growth.
Cause: Localised calcium deficiency in the inner leaves during rapid growth, often triggered by heat causing excessively fast growth rates. Common in warm coastal regions including the Mid North Coast.
Season: Spring, Summer
Tomato Big Bud Disease
Disease — Affects: Tomato, Capsicum, Carrot, Potato
Flowers enlarged and green, petals replaced by leaf-like structures. Stems may be excessively branched. Fruit fails to develop normally. The flower looks more like a bud of leaves than a flower.
Cause: Phytoplasma, a bacterial-like organism spread by Tomato Potato Psyllid (Bactericera cockerelli) in Australia. Found in eastern and south-eastern Australia.
Season: Spring, Summer
Natural remedies: Neem Oil Spray
Tomato Hornworm (Tobacco Hornworm)
Pest — Affects: Tomato, Capsicum, Eggplant, Potato
Large sections of foliage stripped rapidly, often from the top of the plant down. Dark green or black droppings on leaves below are a reliable sign. The caterpillars are large but perfectly camouflaged against green stems.
Cause: Larva of the Hawk Moth (Manduca spp.). Found across Australia, particularly in warm coastal and subtropical regions. Common on the NSW Mid North Coast through summer.
Season: Spring, Summer
Natural remedies: Bt Spray (Bacillus thuringiensis), Neem Oil Spray
Tomato Mosaic Virus
Disease — Affects: Tomato, Capsicum, Eggplant, Cucumber, Spinach
Mottled light and dark green patterning on leaves, leaf distortion, and curling. Growth is stunted. Fruit may be deformed, have internal browning, or ripen unevenly. No effective treatment once infected.
Cause: Tomato Mosaic Virus (ToMV) and related strains. Spread by aphids and by physical contact (hands, tools, clothing). Found across all of Australia. The aphid connection makes it particularly prevalent in areas with high aphid pressure.
Season: Spring, Summer
Natural remedies: Neem Oil Spray
Once you see mosaic virus in a plant, remove and dispose of it — don't compost it. Controlling aphids is the main preventative strategy.
Tomato Potato Psyllid
Pest — Affects: Tomato, Potato, Capsicum, Eggplant, Tamarillo
Yellowing and purpling of leaves (psyllid yellows symptom). Stunted growth. Heavily attacked plants have raised leaf margins and general yellowing from the base up. White waxy granules on leaf undersides from nymphs.
Cause: Tomato Potato Psyllid (Bactericera cockerelli). An invasive pest in New Zealand that arrived in Australia and is spreading. Currently established in WA, with surveillance ongoing in eastern states.
Season: Spring, Summer
Natural remedies: Neem Oil Spray, Soap Spray
Tomato Spotted Wilt Virus
Disease — Affects: Tomato, Capsicum, Lettuce, Peanut, Dahlia, Zinnia
Bronze or purplish discolouration of young leaves, stunting, dark streaking on stems. Fruit shows yellow spots and rings, or bronze-brown surface markings. Growth tips may die back.
Cause: Tomato Spotted Wilt Virus (TSWV), spread exclusively by thrips — primarily Western Flower Thrips. Found across all of Australia. Thrips can spread it rapidly across a garden.
Season: Spring, Summer
Natural remedies: Neem Oil Spray, Soap Spray
Remove infected plants immediately to prevent spread. The priority is reducing thrips populations — that's what limits the virus.
Tomato Yellow Leaf Curl Virus
Disease — Affects: Tomato
Upward curling and yellowing of leaves, particularly new growth. Plants are severely stunted. Flowers may drop. Fruit set is poor. Infected plants rarely recover productive capacity.
Cause: Tomato Yellow Leaf Curl Virus (TYLCV), spread by the Silverleaf Whitefly (Bemisia tabaci). Found across tropical and subtropical Australia. Increasingly common in coastal NSW as whitefly populations have spread.
Season: Spring, Summer
Natural remedies: Neem Oil Spray, Soap Spray
Remove infected plants. Controlling whitefly is the prevention strategy — this is another reason to manage whitefly populations consistently through summer.
Two-spotted Ladybird (Pest Species)
Pest — Affects: Pumpkin, Zucchini, Cucumber, Potato
Irregular pale patches or windows on leaf surfaces where the upper or lower epidermis has been scraped away. Affects cucurbits. Entire leaves can look bleached and papery in severe infestations.
Cause: Two-Spotted Ladybird (Illeis galbula). A native Australian species that feeds on powdery mildew and soft leaf tissue. Found across eastern Australia.
Season: Spring, Summer
Natural remedies: Neem Oil Spray
Two-spotted Mite on Strawberry
Pest — Affects: Strawberry
Leaves become bronzed and stippled. Fine webbing on leaf undersides in heavy infestations. Plant growth is stunted and fruit production drops. Can devastate a strawberry planting in warm dry conditions.
Cause: Two-spotted Spider Mite (Tetranychus urticae). Found across all of Australia. Particularly damaging to strawberries in warm dry conditions.
Season: Spring, Summer
Natural remedies: Neem Oil Spray, Soap Spray
Verticillium Wilt
Disease — Affects: Tomato, Capsicum, Eggplant, Potato, Strawberry
One-sided yellowing of older leaves that progresses upward. Wilting during the heat of the day, partially recovering at night. Brown vascular discolouration in the stem when cut. Slower progression than Fusarium wilt.
Cause: Verticillium dahliae and V. albo-atrum. Soil-borne fungi. Found across cooler regions of Australia — more common in Victoria, SA, and cooler parts of NSW.
Season: Spring, Autumn
Natural remedies: Worm Castings Soil Drench
Waterlogging
Environmental — Affects: Most vegetables, Tomato, Beans, Peas, Strawberry
Yellowing leaves, wilting despite moist soil, slow growth, root discolouration. Plants may look drought-stressed even though the soil is wet. Prolonged waterlogging kills roots through oxygen deprivation.
Cause: Excess water in the soil displacing oxygen from the root zone. Roots need oxygen to function. Heavy clay soils, compacted beds, and low-lying areas are most susceptible.
Season: Autumn, Winter, Spring
The Mid North Coast gets significant rainfall. Raised beds are the long-term answer for vegetables in a clay-heavy soil.
Whiptail (Molybdenum Deficiency)
Environmental — Affects: Cauliflower, Broccoli, Cabbage
Leaves become narrow, strap-like, or reduced to the midrib only. New growth is malformed and plant development is severely affected. The characteristic 'whip' shape of affected leaves is unmistakable.
Cause: Molybdenum deficiency, almost always caused by acidic soil (pH below 6) that makes molybdenum unavailable to the plant. Found across acidic-soil regions of Australia.
Season: Autumn, Winter
White Cabbage Aphid
Pest — Affects: Cabbage, Broccoli, Brussels Sprouts, Kale, Cauliflower
Dense grey-white waxy colonies in the heart of brassica plants and on leaf undersides. Yellowing and stunting of the affected growing point. The aphids are powder-grey and heavily wax-covered.
Cause: Cabbage Aphid (Brevicoryne brassicae). Specific to brassica crops. Found across all of Australia. A particular problem in the brassica growing season on the Mid North Coast.
Season: Autumn, Winter
Natural remedies: Soap Spray, Neem Oil Spray
Whitefly
Pest — Affects: Tomato, Capsicum, Eggplant, Cucumber, Beans, Sweet Potato, Cabbage
Clouds of tiny white insects erupt when foliage is disturbed. Leaves yellow and become sticky with honeydew. Sooty mould often follows on the sticky residue. Plant growth slows.
Cause: Silverleaf Whitefly (Bemisia tabaci) and Greenhouse Whitefly (Trialeurodes vaporariorum). Major pest of warm-climate vegetable gardens across coastal and tropical Australia. A significant problem on the Mid North Coast through summer.
Season: Spring, Summer, Autumn
Natural remedies: Neem Oil Spray, Soap Spray, Garlic Spray
Wireworm
Pest — Affects: Potato, Carrot, Onion, Corn, Beans, Seedlings
Holes tunnelled through root vegetables, particularly potatoes and carrots. Seeds may fail to germinate — eaten before emergence. Seedlings collapse as roots are severed.
Cause: Larvae of Click Beetles (Agriotes and related species). Found across agricultural land in Australia, particularly in recently cultivated pasture or lawn. Worse in the first year or two after converting a grassy area to a garden bed.
Season: Spring, Summer
Natural remedies: Diatomaceous Earth
