How to grow tomatoes

Growing tomatoes is one of the most rewarding gardening activities and an easy way to start children gardening. They are easy to grow and quickly provide the freshest of tasty results. Tomatoes can be grown from seed or are readily available as seedlings.


Fight Heart Disease

Medical research shows that tomatoes could be the key to preventing blood clots that cause heart disease and strokes. That’s because the yellow jelly which surrounds tomato seeds helps keep platelets in the blood from clumping together, therefore eliminating the risks.

When to Plant

The weather rather than the calendar date is the determining factor. They generally need three months of warm, frost free weather to produce well. Labour weekend is the traditional time for planting tomatoes but they can be planted outdoors as soon as conditions allow, usually any-time from September onwards.

Soil and Position

Tomatoes need plenty of sunshine. Any free draining soil which is rich in organic matter is ideal. Tall varieties need protection from strong winds. Against a wall, fence or trellis is ideal. Prepare the soil by adding liberal amounts of compost and digging through deeply.

Growing Tomatoes in Containers

Tomatoes are happy in containers or planter bags. Stake and train as you would plants grown in the garden. Use a specific container planting mix. Take extra care with watering do not let the soil dry out. Liquid feed fortnightly. Smaller growing, less vigorous varieties are easiest to manage in pots eg: Dwarf, Sweet 100, Russian Red.


Plant seedling tomatoes at least 40cm apart. Prepare the soil as per above. Water the plant in its container and allow to drain. Plant without disturbing the rootball. Firm the soil gently. Seedling plants can be planted in the soil about 2cm further up the stem than it was in the pot. If planting seedlings from a punnet, first remove from the punnet then gently separate the seedlings.

Tomates au jardinStaking

It is a good idea to position stakes for all varieties at planting time to avoid damaging the roots later on. Overhead wires with strings to climb up can also be used.


This depends on the type and variety of tomato. Tall varieties need pruning to aid air circulation (which prevents disease), to let in maximum light and to concentrate the plant’s energy on the main leaf structure and the fruit. As the plant grows remove all lateral growths as soon as they appear.

These appear between each leaf and the main stem. When the plant has six or seven good trusses of fruit, pinch out the growing tip. This is called “Stopping” and encourages the plant to put it’s energy into developing fruit. Dwarf varieties do not need pruning or staking.

Feeding and Watering

Tomatoes with their rapid growth rate are both thirsty and hungry. It is very important to water regularly in dry weather. The plants must not be allowed to dry out. Mulching is an excellent way of conserving moisture in summer. Compost is ideal for this purpose. As plants grow and become loaded with fruit their requirement for water will increase. Once the small fruit appears to supplement your initial ground preparation with a fortnightly feed of a balanced fertiliser such as Phostrogen Tomato Fertiliser. This fertiliser is high in potassium to encourage fruit set. Water thoroughly after feeding.


It is a good idea to pick fruit before it is fully coloured and still quite firm. This helps fruit keep longer and relieves the plant of its load allowing it to keep on the job of producing more crops.

Pests and Diseases

Minimise problems by:

  • Changing the site or replacing the soil of sites used previously for growing tomatoes.
  • Pruning to encourage air circulation which helps deter diseases.
  • Remove foliage or fruit showing signs of disease.
  • Planting grafted tomatoes. These are grown on disease resistant rootstock.
  • To control blight spray fortnightly with Champ DP, or make that a weekly spray if it`s hot humid weather.
  • For white fly spray with Mavrik.

Limitation of Liability

This article has been produced to provide basic information. As this information is generalised Mitre10 (& GrownUps) is not responsible for the application of the principles in any particular case, as the contents of this project may need to be modified for the particular site and circumstances. Consumers should always ensure that they comply with any local body bylaws that pertain to any construction project and consult a qualified tradesperson where expert services are required.