Tomatoes prefer a well-drained soil or growing medium which encourages a deep and healthy root system.
Organic matter is essential to develop and maintain good soil structure – well-made garden compost is ideal. The best way to find out the nutrient status of your soil is to have it analysed – The RHS offers a soil analysis service. Tomatoes prefer a soil pH in the range 6.0 - 6.5 i.e. slightly acid, but this is a bit too low for some crops such as lettuce and brassicas, so you might need to aim at between 6.5 and 7.0. However don’t apply lime immediately before planting tomatoes unless the pH is below 6.0.
You should aim to apply all of the Phosphorus and Magnesium needed for the whole season, part of the Potassium (also known as potash) but little or no Nitrogen, or else you will get lots of lush growth and your flowers won’t ‘set’ fruit. Don’t forget that your garden compost should contain a lot of nutrients. In the absence of a soil analysis, apply a high-potash fertilizer according to the recommendations on the packet; fork in the fertilizer or compost to a depth of about 20cm.
If you are using grow bags make sure they are placed on a firm surface, slightly sloping away from your path. If you’re using pots or other containers, the bigger the better, not less than 12 litres per plant; fill them with a good quality growing medium recommended for containers.
Tomatoes need about 0.4 sq m (4 square feet) per plant, so you can plant them 60cm X 60cm (2ft X 2ft) or 46cm (18 inches) between in the row and 87cm (2½ ft) between rows.
By the time conditions are suitable for planting, you may be able to see the first truss in bud or just opening. Your plants may need a small cane to support them if they start to flop over. It is very important to remove the first truss shoot early so that you get a strong first truss. This is a side-shoot that grows in the axil below the first truss. For details of how to remove side-shoots see our helpful video on YouTube: Twisting Tomatoes - (training and side-shooting tomatoes).
Make a hole with a trowel, and plant as deep as possible without burying any of the leaves, or covering the graft union (if your plants are grafted).
Did You Know?
British Tomato growers use an army of over 100 million beneficial predatory bugs to help balance glasshouse ecosystems where pests are controlled by predators and so are present at a level below those causing economic damage and thus reducing, to virtually zero, the need to use any pesticides which if they are will be primarily biological in origin.