Tomato Growing Guide
Main crop in spring, possible autumn crop. Need support.
Overview
Planting Calendar
| Planting months | 1,2,8,9,10,11,12 |
|---|---|
| Seed tray (indoors) | 8,9,10,11,12 |
| Transplant out | 1,2,10,11,12 |
| Direct sow | 1,10,11,12 |
| Days to harvest | 80 days |
Growing Conditions
| Temperature | 20-30 |
|---|---|
| Soil temp | 16–35°C |
| Spacing | 45-60 |
| Water per day | 2.0 L/plant |
| Plant type | Fruiting Crop |
Soil Requirements
| pH range | 6.0–7.0 (ideal 6.5) |
|---|---|
| Soil type | Deep, rich, well-structured loam with high organic matter. Tomatoes are deep-rooted and reward thorough soil preparation. |
| Drainage | free-draining |
Preparation: Dig to 40-50cm and incorporate two buckets of aged compost or well-rotted manure per square metre. Add gypsum to clay soils at 200g/m2. Test pH and adjust with lime or sulphur. Allow 2 weeks before planting.
Avoid: Avoid freshly manured beds (too much nitrogen, risk of disease). Avoid compacted or poorly drained spots. Do not plant in the same bed as the previous season (disease build-up). Avoid very alkaline or very acidic soil.
Watering
Method: Deep watering at the base; drip irrigation ideal. Never overhead. Water into the root zone, not onto foliage.
| Summer | Every 1-2 days in temperatures above 30°C. Daily during heatwaves. |
|---|---|
| Winter | Every 3-4 days. Reduce significantly once fruiting ends. |
| Depth | 30 cm |
Critical periods: Flowering and fruit set (water stress causes flower drop); fruit development (uneven watering causes blossom end rot and splitting); transplanting week (daily until established).
Companion Plants
Asparagus, Chervil, Carrot, Celery, Chives, Parsley, Marigold, Basil
Growing Stages
What to do: Sow seeds 6mm deep in seed-raising mix. Keep at 20-29°C. Keep mix consistently moist but not wet. Place in a warm, bright spot or use a heat mat.
Watch for: Damping off (seedlings collapsing at soil level) from overwatering or poor air circulation. No emergence after 14 days suggests soil too cold or seed too old.
What to do: Pot on to 10cm pots once two true leaves appear. Water from base to strengthen stems. Begin weekly dilute liquid feed. Harden off outdoors for one week before transplanting.
Watch for: Leggy, pale seedlings indicate insufficient light. Damping off indicates overwatering. Hold off transplanting until night temperatures stay above 15°C.
What to do: Transplant into deeply prepared bed. Bury stem up to the lowest leaves (adventitious roots develop). Install stakes or cages immediately. Water in well. Apply mulch 7-10cm deep around base.
Watch for: Wilting in mid-afternoon is normal in heat. Persistent morning wilt indicates drought stress. Watch for leaf curl, aphids, and early signs of fungal leaf spot.
What to do: Pinch out suckers on indeterminate varieties weekly. Feed with low-nitrogen, potassium-rich fertiliser. Gently shake flower trusses on still days to aid pollination. Ensure consistent watering.
Watch for: Flower drop indicates temperature extremes (above 35°C or below 10°C at night), water stress, or insufficient pollination. First signs of blossom end rot.
What to do: Continue potassium-rich feeding fortnightly. Maintain consistent soil moisture. Remove any yellowing lower leaves for airflow. Inspect fruit for entry holes (Helicoverpa).
Watch for: Blossom end rot on developing fruit. Fruit cracking from uneven watering. Fungal disease spreading up the plant. Helicoverpa entry holes near the stem end.
What to do: Begin harvesting as fruit reaches full colour. Pick regularly to encourage continued production. Cut or twist fruit from the truss without pulling.
Watch for: Over-ripe fruit splits and attracts fruit fly. Under-ripe fruit picked in hot weather will ripen off the plant on a bench.
Fertilising
Strategy for Fruiting Crop crops.
Strategy
Start with nitrogen for early leafy growth, then SWITCH to potassium once flowering starts to drive flowers and fruit. The classic tomato feeding pattern.
Key Nutrients
Nitrogen early; then potassium (K) high through flowering/fruiting; phosphorus moderate; calcium important.
How Often
Nitrogen feed early; from first flowers, switch to weekly/fortnightly high-potassium liquid feeds.
Organic Fertilisers
Compost + aged manure at planting; then a high-potassium feed (tomato/fruit & flower food, or comfrey tea) from first flowers. Eggshells/lime/gypsum for calcium to limit blossom-end rot.
Kitchen Scraps
Banana skins (compost - potassium), eggshells (slow calcium, crush fine), composted veg scraps. Wood ash sparingly for potassium.
Homemade Liquid Feeds
Comfrey tea (high K) is the standout DIY feed from flowering onward; fish emulsion early for leafy establishment.
What to Avoid
Avoid continued high nitrogen once flowering - you get leaves, not fruit. Keep water EVEN (erratic watering + low calcium = blossom-end rot, splitting).
Nutrient Deficiency Diagnosis
If leaves look off, use this table to identify what the plant is missing.
Calcium (Ca) calcium deficiency / blossom end rot High
Which leaves: Young/new growth first
Symptoms: In developing fruit: dark brown-black, sunken, leathery patch at the blossom end of tomato, capsicum, eggplant, zucchini fruit (blossom end rot). In leaves: new growth is distorted, small, and cupped or hooked downward. Brown spots appear on young leaves and leaf tips. Tip burn on lettuce inner leaves is a classic calcium deficiency symptom.
Fix: Maintain consistent soil moisture with deep, regular watering and thick mulch. Apply liquid calcium products (eco-flo lime, liquid gypsum). Gypsum adds calcium without altering pH. Remove affected fruit so plant redirects resources.
Often confused with: Fungal disease (blossom end rot is not infectious); Boron deficiency (similar distorted new growth); Magnesium deficiency (but Mg affects old leaves); Sunscald on fruit
Boron (B) boron deficiency High
Which leaves: Young/new growth and growing tips first
Symptoms: Growing tips die back; new leaves are small, thick, brittle, and leathery. Leaves at the tip may show yellowing edges or rust-coloured patches. Stems and petioles may crack or feel brittle. Hollow stems in broccoli and cauliflower; rotting or brown heart in beetroot and turnip; cracked stems in celery; small deformed heads in cauliflower; leaf tip dieback in lettuce.
Fix: Apply borax at very low rates - 0.5g per square metre as a soil drench (caution: very narrow margin between deficiency correction and toxicity). Lower soil pH if above 7.0. Seaweed extract contains some boron.
Often confused with: Calcium deficiency (both cause distorted new growth and browning of tips and hearts); Drought stress; Fungal disease in brassica hearts; Hollow stem in broccoli from rapid growth
Nitrogen (N) nitrogen deficiency Medium
Which leaves: Old/lower leaves first
Symptoms: Uniform pale yellowing (chlorosis) starting on lower leaves and spreading upward. Entire plant looks washed out and light green. Stems may be thin and spindly. Older leaves may develop pinkish or reddish tints before dropping. Fruit and foliage are smaller than normal. Growth is slow and stunted.
Fix: Apply blood and bone meal or poultry manure pellets immediately. Liquid fish emulsion or worm castings tea gives faster results. For containers, use a liquid fertiliser with nitrogen fortnightly.
Often confused with: Winter cold or waterlogging; Root damage from nematodes or fungal pathogens; Sulphur deficiency (but sulphur affects new growth first); General overwatering
Potassium (K) potassium deficiency Medium
Which leaves: Old/mature leaves first
Symptoms: Scorched or burnt-looking leaf edges (marginal leaf scorch) starting at the tips, progressing inward. Older leaves turn yellow then brown at the margins. Leaves may curl, crinkle, or roll along the edges. Fruit is small and poorly coloured. Plants are more susceptible to drought and frost. In tomatoes, fruit may ripen unevenly.
Fix: Apply comfrey leaves as mulch (extremely high potassium). Make comfrey liquid fertiliser. Wood ash is a fast-acting organic source but raises pH. Seaweed meal or liquid seaweed provides potassium.
Often confused with: Drought stress or heat scorch (similar marginal leaf burn); Salt damage from over-fertilising; Magnesium deficiency (but Mg shows interveinal yellowing, not marginal scorch); Sucking insect damage
Magnesium (Mg) magnesium deficiency Medium
Which leaves: Old/lower leaves first
Symptoms: Interveinal chlorosis (yellowing between the veins while the veins themselves stay green) on older leaves. Leaves look like a green fishbone pattern on a yellow background. Reddish-brown or purple tints may appear between veins in advanced cases. Older leaves drop prematurely. In tomatoes, the lower leaves yellow first and progressively up the plant.
Fix: Foliar spray of Epsom salts (magnesium sulphate) at 20g per litre of water, applied fortnightly. Soil drench of Epsom salts is slower but effective. Apply dolomite lime to acidic soils. Stop high-potassium feeds if overuse is the cause.
Often confused with: Iron deficiency (but iron affects NEW leaves, not old leaves); Manganese deficiency (affects young leaves); Normal autumn leaf yellowing; Nitrogen deficiency (nitrogen causes uniform yellowing, not interveinal)
Iron (Fe) iron deficiency / iron chlorosis Medium
Which leaves: Young/new growth first
Symptoms: Interveinal chlorosis on youngest leaves, which turn pale yellow to almost white while leaf veins remain distinctly green. Most visually striking deficiency in the garden. In severe cases, entire new leaves turn white. Growth slows and new leaves may be stunted. Brown dead spots can appear between veins in severe cases.
Fix: Apply chelated iron as soil drench or foliar spray for rapid correction. Lower soil pH with sulphur powder. Liquid seaweed extract contains natural chelating agents. Add sulphur or acidic compost around affected plants.
Often confused with: Manganese deficiency (very similar; manganese shows on young-to-middle leaves); Zinc deficiency (also affects new leaves but causes small leaves and rosetting); Sulphur deficiency (uniform yellowing, not interveinal)
Zinc (Zn) zinc deficiency / little leaf Medium
Which leaves: Young/new growth first
Symptoms: New leaves are abnormally small and may be pale green or yellow between the veins. The gaps between nodes become very short, giving a rosette or clustered appearance. Leaves may be narrow and distorted. Brown or bronze spots appear on leaf margins and tips. Shoot tips are stunted. Multiple small leaves cluster at the growing tip (little leaf or rosetting).
Fix: Foliar spray with zinc-containing seaweed or micronutrient fertiliser. Add organic compost. Lower soil pH with sulphur if alkalinity is the cause. Apply rock dust or kelp meal as a slow release source.
Often confused with: Boron deficiency (also causes small deformed new leaves and rosetting); Iron deficiency (interveinal chlorosis on new leaves, but zinc has distinctive small leaf size); Virus infection (mosaic patterns can look similar)
Manganese (Mn) manganese deficiency Medium
Which leaves: Young to middle leaves
Symptoms: Interveinal chlorosis (pale yellow tissue between green veins) on young to middle leaves. Similar to iron and magnesium deficiency but affects upper-to-middle leaves. Tan or sunken necrotic spots may appear in the chlorotic zones. Leaf margins may brown. In severe cases, leaves die and drop.
Fix: Apply manganese sulphate as a foliar spray for rapid correction. Liquid seaweed contains some manganese. Lower soil pH with elemental sulphur. Improve drainage. Add composted seaweed or greensand rock dust.
Often confused with: Iron deficiency (very similar; iron is strictly on newest tip leaves, manganese on slightly older young leaves); Magnesium deficiency (but Mg affects old leaves); Zinc deficiency (zinc shows rosetting and smaller leaf size); Mite or insect damage
Molybdenum (Mo) molybdenum deficiency / whiptail Medium
Which leaves: Older/lower leaves in most vegetables; developing leaves progressively in brassicas
Symptoms: In brassicas: classic whiptail symptom where leaves become narrow, strap-like, and twisted. The leaf blade does not develop properly, leaving only the midrib or a thin strip of leaf tissue. Head formation is inhibited. In legumes and other vegetables: older leaves show faint yellow-green chlorosis with marginal browning. In lettuce and cucurbits: whitish-tan interveinal chlorosis with marginal leaf burn.
Fix: Lime the soil to raise pH above 6.3 - this alone often resolves the deficiency. Apply fritted trace elements that include molybdenum. A foliar spray of sodium molybdate at very low dilution for immediate correction.
Often confused with: Fungal or viral disease causing leaf distortion in brassicas; Nitrogen deficiency (similar chlorosis); Herbicide damage causing leaf distortion; Cabbage aphid damage causing distorted cupped leaves
Phosphorus (P) phosphorus deficiency Low
Which leaves: Old/lower leaves first
Symptoms: Stunted, slow-growing plants with small, dark green leaves. Older leaves develop a reddish-purple or bronze discolouration, most visible on the undersides and along leaf veins. Stems become thin and spindly. Fruit set is poor. In tomato seedlings, the entire plant turns purple underneath when soil is cold.
Fix: Apply blood and bone or bone meal worked into the soil. Rock phosphate is a slow organic source. Raising soil temperature with black plastic mulch will often resolve cold-related purple colouring in seedlings.
Often confused with: Cold stress (purple seedlings from cold soil mimic phosphorus deficiency); Anthocyanin pigmentation in some varieties (normal); Early fungal disease
Sulphur (S) sulphur deficiency Low
Which leaves: Young/new growth first
Symptoms: Uniform pale yellowing of new leaves and growing shoots while older leaves remain green. Entire new leaves turn light green to yellow, not just between veins. Stems are thin, short, and spindly. Petioles and stems may show reddish-purple colouration in tomatoes and potatoes. Growth is slowed. In peas, young leaves curl inward.
Fix: Apply gypsum (calcium sulphate) to soil as a sulphur source that does not alter pH. Epsom salts (magnesium sulphate) adds both sulphur and magnesium. Blood and bone and aged manures contain organic sulphur.
Often confused with: Nitrogen deficiency (most common confusion; nitrogen affects OLD leaves, sulphur affects NEW leaves); Iron deficiency (also affects new leaves; but iron shows interveinal pattern, sulphur is uniform yellowing)
Copper (Cu) copper deficiency Low
Which leaves: Young/new growth first
Symptoms: Young leaves wilt without going yellow first, then turn pale green and begin to curl downward. Tips and upper leaf surfaces develop a distinctive blue-green colouration. Leaves appear limp and lifeless even with adequate water. Growing tips may die back. Onions and leeks may show collapsed, pale leaf tips.
Fix: Apply copper sulphate to soil at low rates (copper is toxic to earthworms at high doses). Poultry manure contains copper. Amino-copper chelates are a gentler option. Lower soil pH if alkalinity is the cause.
Often confused with: Drought stress or heat stress (wilting young leaves looks like underwatering); Root disease causing wilting; Iron or manganese deficiency (interveinal chlorosis in later stages)
Varieties
Tigerella
salad65 days to harvest
Red and orange striped medium tomato. Earlier than most. Good flavour, productive plant. Suits cooler autumn planting in SE QLD.
Seeds: Kings Seeds, Eden Seeds
Tommy Toe
cherry70 days to harvest
Heirloom cherry tomato, very productive in subtropical QLD. Sweet flavour, crack-resistant. Highly recommended for Dayboro climate.
Seeds: Diggers Club, Eden Seeds
Roma
paste75 days to harvest
Meaty paste tomato with low moisture content. Ideal for cooking, sauce and drying. Good disease tolerance. Suits subtropical summers.
Seeds: Diggers Club, Yates
Grosse Lisse
beefsteak80 days to harvest
Classic large Australian beefsteak. Very popular for slicing. Grows well in subtropical conditions. Susceptible to disease in wet seasons.
Seeds: Yates, Kings Seeds
Black Russian
heirloom80 days to harvest
Dark burgundy-black beefsteak with rich, earthy flavour. Very popular at farmers markets. Best in autumn in subtropical QLD.
Seeds: Diggers Club, Eden Seeds
Pests and Diseases
Blight (Early & Late)
DiseaseAlso known as: Tomato blight; potato blight; target spot
How to recognise it
Early blight: brown concentric-ring 'target' spots on older leaves. Late blight: fast greasy grey-brown blotches on leaves/stems, white mould underneath in humid weather, rapidly rotting fruit.
Remedies (1)
Sanitation + copper + airflow + rotation Product Moderate
Ingredients: Registered copper fungicide per label; mulch; pruning tools; rotation plan.
How to make: Mix copper to label.
How to apply: Remove and BIN affected lower leaves promptly. Mulch to stop soil splash. Stake/prune for airflow and water at the base. Apply copper protectant to remaining foliage. Rotate solanaceous crops yearly.
When to use: From first spots; humid/wet weather.
Frequency: Copper every 7-14 days and after rain while at risk.
What not to do: Don't compost blighted material. Don't grow tomatoes/potatoes in the same bed each year. Don't wet foliage late. Late blight can destroy a crop fast - act early.
Safety: Copper per label; wear protection.
Fusarium & Verticillium Wilt
DiseaseAlso known as: Wilt; soil wilt; fusarium wilt; verticillium wilt
How to recognise it
One-sided or whole-plant wilting that doesn't recover with watering; yellowing from lower leaves up; brown staining inside cut stems; soil-borne and persistent.
Remedies (1)
Resistant varieties + rotation + soil health (no cure once infected) Cultural Moderate Edible safe
Ingredients: Disease-resistant seed (look for VFN codes); compost; rotation plan; solarisation plastic.
How to make: No spray - there's no effective organic cure once a plant is infected.
How to apply: Remove and bin infected plants. Plant resistant varieties. Rotate away from susceptible crops for several years. Build soil biology with compost. Solarise badly affected beds in peak summer.
When to use: Prevention is the whole game - plan before planting.
Frequency: Ongoing rotation and soil care.
What not to do: Don't replant susceptible crops in infected soil. Don't compost infected plants in a cool heap. Don't expect sprays to fix it.
Safety: Safe.
Tomato Spotted Wilt Virus
DiseaseAlso known as: TSWV; spotted wilt; bronze wilt; tomato bronzing; virus; thrips-transmitted virus
How to recognise it
Initial symptoms appear on young growth: bronze or coppery discolouration with tiny dark flecks on expanding leaves, giving a metallic sheen. Leaves may develop yellow or pale green ring spots and mottling. Growing tips distort and stunt. Older leaves show necrotic ring spots with concentric dark rings on a yellow background. Fruit develops concentric raised or sunken ring spots, often with colour break (red, yellow and green mottled patches on ripening tomato). Plants infected early produce no usable fruit. Virus cannot be cured. Transmitted exclusively by thrips, most importantly western flower thrips (Frankliniella occidentalis) and onion thrips (Thrips tabaci).
Remedies (4)
Blue sticky traps and reflective mulch for thrips monitoring Trap Supplementary Edible safe
Ingredients: Blue sticky traps (blue catches western flower thrips more effectively than yellow); silver or reflective aluminised mulch film.
How to make: Traps need no preparation. Lay reflective mulch on beds before transplanting, securing edges.
How to apply: Hang blue traps at canopy height, one per 4-5 m row. Lay reflective mulch over bed soil. The reflected UV light disorients thrips and reduces their landing rate on plants.
When to use: Set traps from transplanting. Lay reflective mulch before planting, ideally before thrips pressure begins in early spring (September in subtropical QLD).
Frequency: Check and count traps twice weekly as an early-warning system. Replace traps when covered. Reflective mulch stays in place through the crop life.
What not to do: Do not use yellow traps as the primary thrips monitor - blue is more attractive to western flower thrips.
Safety: Safe. Reflective mulch also reduces soil moisture loss.
Spinosad spray for thrips vector control Spray Moderate Edible safe
Ingredients: Spinosad product (e.g. Yates Success Ultra, Naturalyte) at label rate, typically 1-2 mL per 1 L water for home garden use.
How to make: Measure spinosad into a clean sprayer filled with water. Shake and spray immediately.
How to apply: Spray flowers and young foliage thoroughly - these are where thrips congregate and feed. Apply in the late afternoon or evening when thrips are most active and bees are not foraging.
When to use: When thrips counts on traps indicate rising populations, or when thrips are visible on flowers. Start preventive spraying from first flower open if TSWV has been confirmed nearby.
Frequency: Every 7-10 days. Rotate with soap spray to prevent resistance - do not use spinosad more than 3 times in a row.
What not to do: Do not spray in full sun or heat. Do not apply to open flowers while bees are visiting - spinosad is acutely toxic to bees on contact but breaks down in 1-3 hours on foliage. Do not use spinosad as the only spray in a rotation.
Safety: Certified organic product. Low mammalian toxicity. Follow label withholding periods for edibles (usually 1 day). Avoid bee exposure by spraying at dusk.
Immediate removal and destruction of infected plants Cultural High Edible safe
Ingredients: Thick plastic bags or bin bags for infected plant material.
How to make: No preparation required.
How to apply: As soon as TSWV symptoms are identified on a plant, remove it at the root without shaking it (to avoid dislodging thrips onto nearby plants). Place directly into a sealed bag. Do not compost - bin or bury deeply.
When to use: Immediately when symptoms appear, at any stage of the crop. There is no cure - every day a symptomatic plant remains is another day thrips can acquire and spread the virus.
Frequency: Walk the crop at least twice weekly from seedling stage through to harvest. Remove any symptomatic plant on the spot.
What not to do: Do not leave symptomatic plants in place hoping they recover - TSWV is incurable and the plant is a virus reservoir. Do not compost or leave pulled plants on the soil surface. Do not shake or roughly handle infected plants near healthy ones.
Safety: Wash hands after handling infected plants before touching healthy ones.
Resistant varieties, weed host control, and clean seedlings Cultural High Edible safe
Ingredients: TSWV-resistant tomato varieties (e.g. Mighty Red, Celebrity); clean nursery seedlings; weeding tools.
How to make: No preparation required.
How to apply: Choose certified TSWV-resistant tomato or capsicum varieties when available. Purchase seedlings only from reputable nurseries; inspect for bronzing before buying. Remove sowthistle, capeweed and other common weed hosts within 10 m of the crop.
When to use: Variety choice at planting. Weed control year-round, intensified in spring before the western flower thrips population peaks.
Frequency: Inspect purchased seedlings once before planting. Weed regularly every 2-3 weeks around crop edges.
What not to do: Do not plant seedlings that show any bronzing or distorted tips. Do not assume that because a variety is resistant it is immune - resistance reduces severity but does not guarantee protection under high thrips pressure.
Safety: Safe. Removing weed hosts also benefits overall garden health.
Caterpillars
PestAlso known as: Cabbage white caterpillar; cabbage moth; loopers; grubs; cabbage white larvae; catapillar; catterpillar
How to recognise it
Chewed/skeletonised leaves, ragged holes, dark green/black droppings (frass) on foliage; green or striped grubs on leaf undersides; white or brown moths/butterflies nearby.
Remedies (5)
White butterfly decoys Cultural Supplementary Edible safe
Ingredients: White plastic/painted decoys cut like butterflies, or halved white eggshells on stakes.
How to make: Cut white butterfly shapes or place white eggshells on short stakes around the bed.
How to apply: Place several decoys among brassicas. Cabbage whites are territorial and tend to avoid areas that look occupied.
When to use: Set out in spring before egg-laying peaks.
Frequency: Leave in place; reposition occasionally.
What not to do: Don't rely on this alone - it only reduces numbers. Combine with Bt or netting.
Safety: Safe.
Garlic & chilli deterrent spray Spray Supplementary
Ingredients: 2 garlic bulbs, 2 hot chillies, 1 tbsp (20 mL) vegetable oil, 1 tsp (5 mL) pure soap, 1 L water.
How to make: Blend garlic and chilli with a little water; steep in the 1 L water overnight; strain through cloth; stir in oil and soap. Keep concentrate in fridge up to 1 week.
How to apply: Dilute ~1 part concentrate to 5 parts water; spray onto and under leaves.
When to use: As a deterrent before infestations build, alongside hand-picking.
Frequency: Every 5-7 days and after rain.
What not to do: Don't spray leaves you'll harvest within a day or two (chilli heat). Don't use on seedlings in strong sun - may burn.
Safety: Wear gloves; avoid eyes when handling chilli. Test a few leaves first.
Hand-picking + soapy water Cultural Moderate Edible safe
Ingredients: Hands/gloves, a bucket with ~1 L water + a squirt of pure soap.
How to make: Add a squirt of pure soap to a bucket of water.
How to apply: Inspect early morning; pick caterpillars and scrape yellow egg clusters from leaf undersides into the soapy water.
When to use: Daily to every few days during warm months when moths are active.
Frequency: Daily during heavy infestation.
What not to do: Don't drop picked caterpillars onto soil - they crawl back. Don't miss the egg clusters under leaves.
Safety: Completely chemical-free.
Bacillus thuringiensis (Bt / Dipel) spray Biological High Edible safe
Ingredients: Dipel or eco-caterpillar killer (Bt var. kurstaki). Typical rate ~1 g per 1 L water (always check label).
How to make: Stir Bt powder into water in a clean sprayer at label rate. Add 2 mL eco-oil or a few drops pure soap per litre as a sticker on waxy brassica leaves.
How to apply: Spray upper and lower leaf surfaces to point of run-off, focusing on new growth and leaf undersides where larvae feed.
When to use: At first sign of caterpillars or white/brown moths around plants. Apply late afternoon or evening.
Frequency: Every 7-10 days while active, and reapply after rain.
What not to do: Don't spray in hot midday sun - UV breaks down Bt. Don't store mixed solution - make fresh. Won't kill caterpillars that have stopped feeding or pupated.
Safety: Very safe - only affects caterpillars that eat treated leaves. Harmless to bees, pets, people, ladybirds.
Insect exclusion netting High Edible safe
Ingredients: Fine insect netting (mesh < 2 mm) and hoops or a frame.
How to make: No mixing.
How to apply: Cover the bed with netting on hoops from planting, sealing edges to the ground so moths can't reach plants to lay eggs.
When to use: From transplanting/seedling stage, before moths arrive.
Frequency: Leave in place through the crop; lift only to weed/harvest.
What not to do: Don't leave gaps or let leaves press against the net (moths lay through it). Check no moths are trapped inside.
Safety: Completely safe and very reliable.
Fruit Fly
PestAlso known as: Queensland fruit fly; Qfly; Bactrocera tryoni; Mediterranean fruit fly; medfly
How to recognise it
Small dimpled puncture marks ('stings') on fruit skin, sometimes weeping; fruit rots and drops early; white/cream maggots 5-10 mm inside fruit; adult flies (wasp-like, ~7 mm) around ripening fruit.
Remedies (4)
Male lure traps (monitoring + reduction) Trap Supplementary Edible safe
Ingredients: Wild May or eco-lure male Qfly trap + attractant wick; trap filled with min ~20 mm of liquid.
How to make: Set up trap with attractant per pack.
How to apply: Hang traps in trees to monitor activity and reduce male flies. Use timing to trigger baiting/netting.
When to use: From early in the season before fruit ripens.
Frequency: Refresh lure/liquid per label.
What not to do: Traps alone won't protect a crop - they're a monitoring and reduction aid, not a standalone fix.
Safety: Safe.
Protein bait spray Spray Moderate
Ingredients: Organic-suitable protein bait (e.g. Naturalure / spinosad-based protein bait) mixed per label.
How to make: Mix bait to label rate.
How to apply: Apply as spots/dabs of bait onto foliage or trunk (NOT the fruit). Flies feed on the protein and are killed.
When to use: From early season before fruit ripens; increase as fruit colours.
Frequency: Reapply weekly and after rain.
What not to do: Don't spray bait on fruit you'll eat. Bait alone won't fully protect a crop - combine with netting/hygiene.
Safety: Spot-applied so low exposure; follow label.
Exclusion netting / fruit bagging High Edible safe
Ingredients: Fine exclusion netting (mesh < 2 mm) or individual fruit bags/sleeves/exclusion bags.
How to make: No mixing.
How to apply: Net the whole tree/bed, or bag individual fruit before they start to ripen, so females can't sting the fruit.
When to use: As fruit begins to develop, well before ripening.
Frequency: Leave in place through the fruiting season.
What not to do: Useless once fruit is already stung. Seal netting to the ground/trunk - any gap defeats it.
Safety: Completely safe and the most reliable method.
Garden hygiene / sanitation Cultural High Edible safe
Ingredients: Bucket, black plastic bags, or freezer/microwave.
How to make: No mixing.
How to apply: Collect ALL fallen and stung fruit. Solarise sealed in black plastic in the sun 1-2 weeks, OR freeze 2 days, OR boil/microwave, to kill larvae before disposal.
When to use: Throughout and after the fruiting season.
Frequency: Pick up drops at least twice a week.
What not to do: Never compost or bin untreated infested fruit - larvae pupate in soil and re-emerge. Don't leave fruit rotting on the ground.
Safety: Safe; this is the foundation of all fruit fly control.
Helicoverpa / Corn Earworm / Tomato Grub
PestAlso known as: Heliothis; cotton bollworm; corn earworm; tomato fruitworm; native budworm; Helicoverpa armigera; Helicoverpa punctigera
How to recognise it
Eggs: tiny white-cream ribbed domes (about 0.5 mm), laid singly on flower buds, developing fruit and young foliage. Larvae: highly variable in colour from pale cream to green, pink, reddish-brown or near-black, with a pale side stripe and a darker dorsal stripe; up to 40 mm at maturity. The entry hole into tomato fruit is usually 3-5 mm, surrounded by moist frass; the larva feeds inside the fruit, destroying the core. In sweetcorn the tip of the cob is hollowed and filled with frass. Adults: stout, buff-coloured moths with a wingspan of 35-40 mm; active at dusk and night. Very common in subtropical Queensland from October through April.
Remedies (4)
Regular inspection and hand-removal of eggs and young larvae Cultural Moderate Edible safe
Ingredients: Hands or small paintbrush; bucket with 1 L water and a squirt of pure soap.
How to make: Add soap to the water in the bucket.
How to apply: Inspect flower trusses, buds and young fruit daily at dawn and dusk. Look for tiny ribbed white eggs on flower surfaces and new foliage. Brush eggs and young larvae into the soapy water bucket. Remove and bin any fruit showing a fresh entry hole immediately.
When to use: From first flower open through to harvest. Most important to inspect at first light, when larvae are still on the plant surface rather than inside fruit.
Frequency: Daily during peak summer pressure (November to March in SE QLD). At minimum, inspect every second day.
What not to do: Do not drop picked larvae on soil - they will pupate and emerge as moths. Do not leave holed fruit on the plant or on the soil surface.
Safety: Completely safe.
Trichogramma egg parasitoid release plus insectary companion planting Biological Moderate Edible safe
Ingredients: Commercial Trichogramma pretiosum or T. brassicae sachets (available from biological control suppliers in Australia); insectary plants: dill, coriander allowed to flower, sweet alyssum, cosmos, marigold.
How to make: Trichogramma: open sachets and hang in crop per supplier instructions - no mixing required. Companion plants: sow or transplant around crop edges.
How to apply: Hang Trichogramma sachets at flower height, 1-2 per m2 of crop, so wasps emerge near Helicoverpa egg masses. Establish insectary flowers nearby to sustain adult wasps (they need nectar to survive). Avoid any broad-spectrum sprays in and around the release zone.
When to use: Release Trichogramma at first moth flight, before eggs build up. Companion plants should be established 2-3 weeks before the main crop flowers.
Frequency: Repeat Trichogramma releases every 2 weeks during peak moth season for sustained protection. Companion plants are permanent.
What not to do: Do not apply ANY insecticide (including Btk or spinosad) within 3-5 days of releasing Trichogramma - spray residues will kill the wasps. Do not use if you need to spray regularly; schedule releases in spray-free windows.
Safety: Completely safe. Trichogramma are tiny, non-stinging wasps. Handling sachets requires no protective equipment.
Bacillus thuringiensis var. kurstaki (Btk / Dipel) spray Biological High Edible safe
Ingredients: Dipel DF or eco-caterpillar killer (Btk) at approximately 1-2 g per 1 L water. Add 2 mL eco-oil or a drop of pure soap per litre as a sticker.
How to make: Stir Btk into water and add sticker/soap last. Mix gently and use immediately - do not store mixed solution.
How to apply: Spray flowers, developing fruit trusses, and young foliage where moths lay eggs. Btk must be eaten by the larva before it tunnels into fruit - once inside the fruit it is completely protected. Timing to the egg stage or very young larva (up to 5 mm) is critical.
When to use: From first flower onwards, especially when moths are seen at dusk or eggs are found on buds. In subtropical Queensland, pressure runs from October through April. Apply late afternoon or early evening.
Frequency: Every 5-7 days during moth flight periods; reapply after rain. Increase to every 4 days at peak pressure.
What not to do: Do not apply in hot midday sun - UV degrades Btk within hours. Do not rely on Btk once larvae have entered fruit. Do not store mixed spray - make fresh each time.
Safety: Extremely safe. Btk affects only caterpillars that consume treated foliage. Harmless to bees, beneficial insects, birds, pets, and people. Withholding period: 1 day.
Spinosad spray for high-pressure outbreaks Spray High Edible safe
Ingredients: Spinosad product (e.g. Yates Success Ultra) at label rate, typically 1-2 mL per 1 L water for home garden use.
How to make: Measure spinosad into a clean sprayer filled with water. Shake well and apply immediately.
How to apply: Spray buds, flower heads and young fruit surfaces thoroughly. Focus on the area where petals join the fruit. Apply in the late afternoon or evening.
When to use: When larval numbers exceed what can be managed by hand-picking, or when Btk alone is not keeping pace with the infestation. Rotate with Btk rather than applying spinosad continuously.
Frequency: Every 7-10 days. Do not apply spinosad more than 2-3 consecutive times - rotate back to Btk to manage resistance.
What not to do: Do not spray in heat or sun. Do not spray open flowers while bees are active - spinosad is acutely toxic to bees on contact (allow 3 hours drying time). Do not use spinosad as the sole control measure.
Safety: Certified organic. Low mammalian toxicity. Follow label withholding period (typically 1 day for tomato). Avoid bee exposure by spraying at dusk.
Root-Knot Nematodes
PestAlso known as: Eelworm; root-knot eelworm; nematodes
How to recognise it
Knobbly galls/swellings on roots; stunted, wilting plants that don't respond to feeding/watering; patchy poor growth.
Remedies (1)
Rotation + marigolds + solarisation + organic matter Cultural Moderate Edible safe
Ingredients: French/African marigold seed; clear plastic for solarising; compost.
How to make: No spray - build soil with compost to feed beneficial microbes.
How to apply: Rotate so susceptible crops don't return to the same bed for 2-3 years. Grow a dense block of marigolds as a biofumigant break crop, then dig in. Solarise beds under clear plastic over the hottest 4-6 weeks.
When to use: Plan rotations each season; solarise in peak summer.
Frequency: Ongoing rotation; solarise once over the hottest weeks.
What not to do: Don't replant tomatoes/susceptible crops into the same infested soil. Don't spread infested soil around the garden.
Safety: Safe; entirely cultural.
Spider Mites
PestAlso known as: Two-spotted mite; red spider mite; two spotted mite
How to recognise it
Fine pale stippling/speckling on leaves, leaves turning bronze or dull; very fine webbing on leaf undersides and tips; tiny moving dots (need a hand lens); worse in hot, dry, dusty conditions.
Remedies (2)
Humidity + water spray Cultural Moderate Edible safe
Ingredients: Plain water.
How to make: No mixing.
How to apply: Mist and hose foliage (especially undersides) regularly - mites hate humidity and washing dislodges them.
When to use: During hot, dry spells when stippling/webbing appear.
Frequency: Daily misting during outbreaks.
What not to do: Don't leave plants dusty and water-stressed (mites love that). Avoid wetting foliage late so it stays wet overnight (fungal risk).
Safety: Safe.
Oil spray then predatory mites Biological High Edible safe
Ingredients: Eco-oil 5 mL per 1 L; commercial predatory mites (Phytoseiulus persimilis).
How to make: Use oil per label; release predators per supplier.
How to apply: Knock numbers down with oil first, then release predatory mites to maintain control. Don't do both at once.
When to use: Warmer months when mites active.
Frequency: Oil every 5-7 days short term; predators establish over weeks.
What not to do: Don't keep spraying oil after releasing predators - you'll kill them. Avoid heat stress.
Safety: Predatory mites safe and self-sustaining.
Tomato Potato Psyllid
PestAlso known as: TPP; Bactericera cockerelli; psyllid; potato psyllid; tomato psyllid
How to recognise it
Adults 2-3 mm, winged, look like a tiny cicada with distinctive black-and-white banding on the abdomen. Nymphs are flat, scale-like, yellow-green with a fringe of fine waxy filaments around the body margin. Eggs are tiny and yellow, attached on short stalks along leaf margins. Damage: plants show stunted yellowing growth, leaves curl upward, and a purplish discolouration develops on stems and leaf veins (psyllid yellows). On potato, infected tubers show brown discolouration internally. Psyllid honeydew causes a sticky sheen and secondary sooty mould. Currently established only in Western Australia; suspect finds outside WA must be reported to state agriculture authorities.
Remedies (4)
Yellow sticky traps for monitoring Trap Supplementary Edible safe
Ingredients: Yellow sticky traps (commercial) or yellow card coated with non-drying glue.
How to make: If making DIY traps, cut yellow card to A4 size and coat one side with petroleum jelly or non-drying glue. Commercial traps need no preparation.
How to apply: Hang traps at canopy height, one trap per 5-10 m of row. Check twice weekly and count adults to track population trends.
When to use: From crop establishment through to harvest whenever solanaceous plants are growing. Critical in warm months (October to March in subtropical Queensland).
Frequency: Check and record counts twice weekly. Replace when covered or every 2-3 weeks.
What not to do: Do not rely on traps alone for control - they are a monitoring tool. Do not place traps in windy, exposed positions where they fill with debris.
Safety: Completely safe. Some non-target insects will be caught.
Encourage generalist predators and remove weed hosts Cultural Supplementary Edible safe
Ingredients: Insectary flowers: sweet alyssum, dill, fennel, calendula. Plus weeding tools and crop hygiene practices.
How to make: No spray required. Plant insectary flowers near solanaceous crops. Remove and bin crop residues and weedy solanaceous plants promptly.
How to apply: Establish flowering companion plants through the growing season to attract lacewings, hoverflies and predatory bugs. Remove and destroy all crop debris at the end of the season - do not compost.
When to use: Year-round as a cultural backbone. Intensify weed removal through summer when psyllid populations peak.
Frequency: Ongoing. Weed and remove alternate hosts every 2-4 weeks.
What not to do: Do not plant potatoes or tomatoes near abandoned or weedy solanaceous plants. Do not leave spent plants standing after harvest. Do not apply broad-spectrum insecticides that destroy predators.
Safety: Safe and beneficial.
Kaolin clay barrier spray Moderate Edible safe
Ingredients: Kaolin clay (food-grade, e.g. Surround WP) 25-50 g per 1 L water; 2 mL pure liquid soap as a spreader.
How to make: Add clay to water gradually while stirring; add soap last. Mix well just before use as clay settles quickly.
How to apply: Spray entire plant - upper and lower leaf surfaces, stems - to leave a white powdery film. The particle film irritates and deters psyllid adults from landing and feeding.
When to use: Apply before psyllid pressure builds, from crop establishment or when adults first appear on traps. Most useful as a preventive barrier.
Frequency: Reapply every 7-10 days and after rain that washes off the film. Increase to every 5-7 days under high pressure.
What not to do: Do not use kaolin as the sole control if a confirmed infestation is already established. Do not apply in strong wind (drift loss).
Safety: Food-safe and certified organic. Wash produce before eating. Avoid inhaling clay dust during mixing.
Horticultural oil or soap spray on nymphs Spray Moderate Edible safe
Ingredients: Eco-oil 5 mL per 1 L water; OR 1-2 tsp (5-10 mL) pure liquid soap per 1 L water.
How to make: Measure and add to a clean sprayer filled with water. Shake gently to mix. Make fresh each use.
How to apply: Direct the spray at the undersides of leaves where nymphs settle and feed. Thorough coverage is essential - oil and soap work by contact with the insect, not residual action.
When to use: When nymphs are visible on leaf undersides. Most effective on young, mobile nymphs before waxy secretions thicken.
Frequency: Every 5-7 days while nymphs are present. Alternate with kaolin to reduce resistance risk.
What not to do: Do not spray in temperatures above 30°C or on wilted plants (leaf burn will result). Do not combine oil with sulphur-based sprays (phytotoxic). Adults are harder to kill with contact sprays.
Safety: Eco-oil is registered for edible crops in Australia. Avoid spraying when bees are foraging. Test sensitive varieties first.
Whitefly
PestAlso known as: Greenhouse whitefly; silverleaf whitefly; white fly
How to recognise it
Tiny white moth-like insects that fly up in a cloud when the plant is disturbed; yellowing leaves; sticky honeydew and sooty mould; scale-like nymphs on leaf undersides.
Remedies (3)
Yellow sticky traps Trap Moderate Edible safe
Ingredients: Yellow sticky traps, or yellow card coated with non-drying glue/petroleum jelly.
How to make: If DIY, paint card bright yellow, coat with sticky gel.
How to apply: Hang just above the canopy - whitefly are drawn to yellow and stick.
When to use: From first sign of whitefly clouds.
Frequency: Replace when covered or every few weeks.
What not to do: Monitors and reduces but won't clear a heavy infestation alone. Avoid catching beneficials unnecessarily.
Safety: Safe.
Soap or oil spray (persistent) Spray Moderate
Ingredients: 1-2 tsp (5-10 mL) pure soap per 1 L water, OR eco-oil 5 mL per 1 L.
How to make: Dissolve/shake fresh.
How to apply: Spray leaf undersides thoroughly where adults and nymphs cluster.
When to use: Early morning or evening.
Frequency: Every 3-4 days for 2-3 weeks to break the life cycle.
What not to do: Don't spray in heat. A single spray fails - eggs keep hatching, so persistence is essential.
Safety: Avoid foraging bees; test sensitive plants.
Encourage Encarsia wasp & lacewings Biological Moderate Edible safe
Ingredients: Insectary flowers; commercial Encarsia formosa (parasitic wasp) for greenhouses.
How to make: Release Encarsia per supplier instructions in enclosed/greenhouse settings.
How to apply: Establish nectar plants; release parasitic wasps where appropriate.
When to use: When whitefly first detected; warm season.
Frequency: Ongoing; predators self-sustain in good conditions.
What not to do: Don't spray broad-spectrum insecticides after releasing beneficials.
Safety: Safe and beneficial.
Harvesting
Ready When
Fruit reaches full variety colour (red, yellow, black depending on variety) and yields slightly to gentle pressure. Shoulders near the stem soften slightly. Skin is glossy rather than shiny-tight.
How to Harvest
Twist and lift gently, or snip with scissors or secateurs leaving a short stalk. Handle gently to avoid bruising. Harvest the whole truss once most fruit is ripe, or pick individually.
Storage
Store at room temperature, never in the fridge (cold destroys flavour and texture). Ripen green tomatoes on a bench out of direct sun. Use ripe fruit within 3-5 days. Preserve excess by roasting and freezing or making sauce.
Common Mistakes
Refrigerating tomatoes (kills flavour). Leaving overripe fruit on the plant (invites fruit fly and disease). Picking too early and then complaining they have no taste (let them colour fully on the vine).
Planting windows by climate zone
When exactly to plant depends on your zone. Select yours: