Grow Tomatoes

Tomatoes are consistently ranked as one of the most widely purchased vegetables in many countries, but they are probably number one when it comes to home growing.

Our enthusiasm for home grown tomatoes never wavers, and most home growers can tell you a thing or two about how to grow them. The beauty with tomatoes is that they grow very quickly once established so they deliver great bang for your buck. In one relatively short season they can transform from tiny seedling to fruit-laden plant bearing more fruits than you can comfortably eat yourself. That is, provided you follow some time-tested tips.

Tomato (Solanum lycopersicum) belongs to the Solanaceae (potato) family which includes some others veggies like eggplants, potatoes and peppers. It is usually an upright green, annual plant to around 2 m tall with juicy, red or sometimes yellow, fruit. There are some prostrate and dwarf growing types too, as well as smaller bushes.

General Tips for Growing Tomatoes

In very warm climates and inside greenhouses, tomatoes can be grown throughout the year. In temperate to cool regions they die off in the autumn or winter. Tomatoes are always grown from seed.
Whether for outdoors or greenhouses, tomatoes are best grown in pots to begin with. You can plant seeds at the end of winter. Move seedlings under cover at night or start them off in a cold frame. If seedlings are exposed to cold early on it will retard growth, and those planted later in spring will soon overtake them.

Tomatoes grow best in a slightly acidic rich soil. The optimum soil pH level is 5.8 - 6.0. They use nitrogen in the early stages of growth so prepare beds beforehand by digging in some well-rotted animal manures and pelletised fertilisers. A sprinkling of rock minerals and potash is also helpful because they use plenty of potassium. Once established don't feed with nitrogen because you'll encourage leafy growth at the expense of fruit.

You should never grow them in the same soil two years running because soil-borne pests and diseases build up. Instead rotate beds. Preferably have three veggie beds so they are only grown in the same spot every third year. Avoid growing other members of the potato family in the bed too.

Whilst tomatoes enjoy a sunny position in temperate climates they need shade form harsh sun in the middle of the day. Very strong sunlight can cause wilting and burning of fruit and foliage. Shade cloth is recommended under these conditions. Tomatoes also need protection from strong winds which can damage stems and flowers.

Seedlings will flower after about 4-6 weeks. Tomatoes are insect pollinated. Under glass you may need to shake plants to distribute pollen, or brush flowers with a small paintbrush. Air from fans will also work.

Once you see the first fruit form apply a specially formulated tomato fertiliser and continue to do this fortnightly, or as recommended. For a continuous fruit supply, try growing some late and early cropping varieties together.

If you follow these tips you can avoid most of the tomato diseases and encourage strong plants which are less susceptible to damage from insect attacks.

Three Different Ways to Grow Tomatoes

1) In Pots
You can grow any tomatoes in pots. Just be sure to go for large pots e.g. 15-20 litre capacity to allow for a deep root run. If unsure, opt for the largest size available. Be mindful that you'll need to water pots more often than plants in the ground, but make sure they have adequate drainage otherwise the roots will rot. Dwarf varieties of tomato make good container plants. There are also some cultivars intended to thrive in pot culture. Some to try include 'Micro Tom', 'Tiny Tim' and 'Red Robin', 'Patio Prize' and 'Cherry Falls'.

2) In the Ground
Most people grow their tomatoes in the ground because you can grow whatever you want. The advantage here is that the roots are not restricted so can spread and grow deeply, so the plants and fruits can reach their optimum size. You can grow some of the larger vines and those with heavy fruits like beefsteaks and many of the truss tomatoes. The main disadvantage is that they may be exposed to extremes of weather. However, if you grow them in raised beds or mounds, you can avoid problems with drainage during heavy rain.

3) Hydroponics
In hydroponic systems, Nutrient Film Technique is widely used by commercial growers where the plants are grown with their roots lowered into channels through which is passed nutrient solution. Gravel beds or pots containing aggregate work well too. These are easier and cheaper to set up and so are widely adopted by home hydroponics growers.

Given that the plants are not grown in soil, hydroponic tomatoes must be supplied with nutrients diluted in water. It is often difficult to grow two different species of plants side by side in the same system in hydroponics because different plants have different growing requirements. For example, tomatoes need a different nutrient mix for optimum fruit production to what lettuces need for producing a large tight leafy heart. So, your best bet would be to grow only tomatoes in the one system.

Pruning Tomatoes

Pruning tomatoes is not essential but it can help to increase fruit yields. Different plants respond differently to pruning.
Determinate tomatoes - these are varieties that set a limited amount of fruit before they die. They do not need to be pruned. All that is required is to remove 'suckers' which are the new stems that start to emerge between side shoots and the main stem. These should only be removed below the first flower cluster. If you prune anything above, you are likely to reduce fruit yield. To remove suckers, simply pinch them out by hand.

Indeterminate tomatoes - these are varieties that continue to set fruit up until they die when temperatures cool at the end of the season. They often have more than one stem. Most growers recommend removing any side stems that emerge before the first flower cluster so that the energy goes into the main stem. After that, you can allow up to three further stems above the first flower cluster, one at each successive node. In this case, remove any suckers which emerge above the first flower cluster.

Suckers take energy away from the main stem and side stems. If they are left on the plant they tend to bear inferior fruit. Removal of suckers encourages earlier fruit production and larger fruit because there is less overcrowding of leaves so more sunlight is converted into energy for fruit growth.

Staking Tomatoes

Tomatoes require strong support, and the plants must be trained up a trellis, stakes, or some sort of overhead support system. This is especially beneficial to indeterminate tomato varieties which can become laden with fruit and consequently very heavy.

Staking is best done at the same time that seedlings are planted out to avoid disturbing the roots later on. One 2m stake per plant is enough. If you can grow them up a trellis, that's just as good. Allow about 50-60cm between plants. Pinch off the bottom few leaves and plant the seedlings about halfway up the stem. This encourages a strong root system to develop.

As well as supporting the plants, staking allows good air circulation around plants which reduces the risk of diseases spreading. It also keeps leaves and fruits off the ground where they are more likely to be attacked by pests and diseases. Staking means you can have more plants by growing them upwards and it exposes leaves to sunlight to once again produce more sugars for growth. Staked plants will need to be mulched since the exposed soil will dry out quickly beneath them.

What Type?

Generally cherry type tomatoes with smaller fruits are easier to grow.
Cultivars do vary in taste hardiness and disease resistance.

General Tips for Growing Tomatoes

Three Different Ways to Grow Tomatoes

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