Tomatoes are among the most popular and rewarding crops for vegie patch. While all fruit and vegetables taste better picked fresh from the garden, tomatoes are in a class of their own. The flavour of a ripe, homegrown tomato picked on a warm summer day is hard to beat.
Homegrown tomatoes are packed with goodness. Tomatoes provide lycopene, which is an antioxidant found in red fruit, along with vitamins A and C, carotene and dietary fibre. They consist of approximately 94.5% of water.
Tomatoes originated in South and Central America and are part of the Solanaceae or nightshade family, which also includes potato, tobacco and chilli. First domesticated by the Aztecs before 500BC, there are now believed to be more than 10,000 tomato cultivars.
Tomatoes are one of the most versatile vegetables, served hot or cold in yummy salads, sandwiches, sauces, soups, pasta, casseroles or on top of your favourite pizza.
Follow our seven easy steps to successful tomato harvest including tips along the way.
When to plant.
Tomatoes can be grown in most parts of Australia. Check with garden centres and hardware stores for varieties available in your local area.
- In subtropical and tropical climates tomatoes can be planted and grown year-round, but are most successful during the cooler months of the year
- In cool and temperate climates grow tomatoes in the warmest parts of the year, planting out around October or November. Seeds can be sown from late winter onwards, but seedlings should not be planted out until the soil has begun to warm and all chance of frost has passed. If the weather does turn cold, cover plants overnight to protect them from frost.
- In warm temperate areas tomatoes are planted from August onwards. Make several plantings through spring and early summer to keep the fruit coming well into autumn.
Location.
- They grow best in full sun (or with light afternoon shade in hotter climates). Protect young seedlings with shade cloth.
- In smaller spaces or in containers select patio tomatoes, which are small, sturdy plants that don’t need large stakes and can grow without support, or cascading or tumbling varieties that can be grown to spill over the edge of a pot or raised garden bed. Cherry-style tomatoes have small fruit but form large plants.
- Do not plant tomatoes in the same location as last season, as this can expose tomatoes to soil-borne diseases.
- Companion plant with basil, parsley, garlic, marigolds and nasturtiums.
Soil
Get the soil right to harvest a bumper crop of delicious, juicy tomatoes.
Follow our steps for easy soil preparation.
- Tomatoes prefer a slightly acidic to neutral, light, well-drained soil but will also grow well in slightly alkaline soil.
- Dig in compost like Seasol Super Compost or well-rotted manure before planting or apply Seasol Liquid Compost.
- In areas with heavy or poorly drained soils, grow tomatoes in raised garden beds.
- A soil rich in nutrients helps build strong plants so add Seasol Plant + Soil Booster (100g per square metre) and a fertiliser such as PowerFeed Controlled Release Tomatoes & Vegetables.
- Water in well and let the soil rest for a week or two.
Step 1 – Sowing seeds.
- Grow from seed sown into individual seed cells or punnets to transplant in around six weeks.
- Press two or three seeds about 1-2cm down into moist seed raising mix such as Seasol Seed Raising and Cutting Mix for improved germination.
- Water in well with Seasol GOLD or Seasol as this will help to increase seed germination rates. Soil should be moist but not wet, so check soil moisture daily to ensure tomato seeds have the right conditions to germinate.
- Tomatoes can be grown in individual 10-15cm pots or large containers. Continue to shelter until conditions warm and all threat of frost has passed before moving seedlings outside.
Step 2 – Germination.
- Tomatoes need warm conditions to germinate (16°C and above). Expect germination in 6-14 days (slower rates in colder conditions).
- For faster seed germination rates in seed trays, put them inside on a heating pad.
- When tomatoes sprout, they only have two leaves. These seedlings leaves look like two narrow leaves on either side of the stem.
- Water gently and apply Seasol GOLD or Seasol weekly (mix 30mL of concentrate per 9 litres of water) as this will help to stimulate strong root development and healthy growth.
Step 3 – Baby tomato seedlings.
- About two weeks after the seed leaves have opened, the true leaves will appear; these are the first tomato leaves.
- If overcrowding occurs, select the strongest seedling and thin out or transplant the rest.
- Use scissors or tweezers to thin out seedlings to avoid disturbing young roots.
- Tomato seedlings need a lot of nutrients to grow to produce a tasty bumper crop so liquid feed with PowerFeed PRO SERIES for Tomatoes & Vegetables every 2 weeks. Increase the application rates from 20mL to 50mL of concentrate per 9 litres of water as the plants mature.
- Check soil moisture daily and water as needed.
Step 4 – Planting out tomato seedlings.
- Transplant homegrown seedlings when they form two to three true leaves and are large enough to handle. Space 50-60cm apart (depending on variety) in rows at least 60cm apart (greater spacing makes it easier to manage and train vines).
- Most tomatoes are tall-growing vines (indeterminate) that need plenty of space and the support of 2-3m high stakes, a tripod or trellis to grow strong and healthy.
- Where seedlings have been purchased, plant according to the directions on the plant tag.
- Seedlings or grafted plants should be planted deeply, burying the bottom few centimetres of the stem in the soil to encourage extra root formation which not only gives the plant extra support but also can source extra nutrients and water.
- Check the moisture level of the soil daily and water when needed.
Step 5 – Tomato plant growth.
- Tie growth to supports using a soft tie so as not to damage the stem. Tie below a leaf stalk or flower cluster.
- Control the bushiness of the plant by pruning out laterals (shoots from the leaf axils). This also allows more sunlight to reach developing fruit.
- As the plant reaches the top of the stake, it can be tip pruned to control its size.
- Every 6-8 weeks apply another application of PowerFeed Controlled Release Tomatoes & Vegetables to produce a bumper crop of tasty tomatoes and to revitalise depleted soils. Remember to water it in thoroughly after application.
Step 6 – Tomato flower & fruit growth.
- Remove weeds as they appear as they compete for space and nutrients.
- Mulching around each plant suppresses weeds and helps retain soil moisture and can prevent the spread of mites to the leaves.
- Fruiting quickly follows flowering and will form in 12-20 weeks from sowing seed.
- As flowers begin, apply PowerFeed PRO SERIES for Tomatoes & Vegetables and Seasol GOLD or Seasol weekly.
Step 7 – Tomato harvest.
- In fruit fly zones begin to protect fruit as soon as it is fully sized and well before it ripens.
- Green fruit ripen indoors but flavour is at its best when tomatoes are vine ripened.
- Healthy tomato plants continue to fruit and grow until cold conditions halt growth.
- Keep tomato plants healthy by removing dead and diseased leaves and stems. This will also open up air circulation around the plant.
Things to watch out for……
- Fruit fly These pests (Queensland fruit fly and medfly), which are found in all parts of Australia except South Australia, Tasmania and Victoria, can ruin tomato crops. To protect tomatoes as they ripen, use exclusion netting or bags on plants and fruit or pick fruit to ripen indoors. Renew baited fruit fly traps every three months or apply fruit fly bait sprays regularly to plants (follow the instructions on the container).
- Tomato russet mite While this tiny mite is hard to see, its damage is obvious particularly in hot weather. Leaves start to brown and die from the base of the plant moving upwards. It can also cause corky damage to fruit. Control with regular applications of wettable sulphur. Removing lower leaves can also slow the attack.
- Blossom end rot Water-stressed tomatoes fail to take up enough calcium from the soil and their fruit can be affected by blossom end rot, which causes brown, leathery patches to form at the base of the fruit. Increase frequency of watering.
- Target spot Brown spots and yellowing leaves indicate the fungal disease known as target spot, which can also spread to stems and fruit. Control with registered fungicides. Crop rotation is important to control this disease, which also attacks potatoes and weeds in the Solanaceae family.
- Tomato viruses There are a range of viruses that cause tomato plants to wilt or die back. Most are also found on other Solanaceae plants including potatoes and weeds. Sap-sucking insects such as thrips can spread viral diseases. Manage by following crop rotation (not growing Solanaceae crops in the same beds in successive seasons), controlling weeds and controlling pests. Remove any affected plants. There are no chemical controls
- Tomato ripening Tomatoes may stop flowering and fruiting when temperatures rise above 35°C however, when the temperatures drop below this level, they’ll return to productivity.
