How to Support and Train Tomatoes
Supporting tomatoes keeps stems upright, improves airflow and makes fruit easier to pick. The right method depends on whether plants are cordon or bush types and whether they grow outdoors, in a greenhouse or in a polytunnel. Put supports in place early, before roots and stems make the job awkward.
Identify the tomato's growth habit before choosing a support. Cordon tomatoes grow tall and need a strong cane, string or trellis system to carry one main stem. Bush tomatoes are shorter but often become wide and heavy with fruit, so they benefit from cages, short stakes or a low framework that supports branches without pruning them. Read the plant label and keep it with the crop until you are certain. Plan spacing before planting, allowing enough room to reach each plant for watering, tying and harvesting. Crowded plants are harder to train and remain damp for longer after rain, reducing airflow around leaves.
For outdoor cordon tomatoes, push a sturdy cane into the soil before or at planting, keeping it a few centimetres away from the root ball. Aim for a cane tall enough to support the mature plant, with at least 30 cm firmly in the ground. On exposed sites, use several canes linked by horizontal twine or a simple frame rather than relying on one slender support. In a greenhouse, suspend strong string from a secure overhead bar and tie it loosely at the base of each plant. Check that the structure can carry mature, fruit-laden stems before training begins.
Tie stems with soft garden twine, reusable plant ties or strips of soft material. Make a loose figure-of-eight, with one loop around the cane and the other around the stem, so the stem is not rubbed or constricted. Add ties every 20 to 30 cm as cordon plants grow. Do not use thin wire or tight knots. When training on a string, wind the stem gently around the string as it lengthens, or use loose clips intended for the purpose. Support stems after watering, when they are flexible, but avoid handling them roughly in very hot or cold conditions.
Pinch out sideshoots only on cordon tomatoes, not bush types. This keeps a cordon plant to one leader and makes cane or string training straightforward. Bush tomatoes should retain their side growth, so guide outer branches onto a cage or low support instead. Check supports weekly once flowers and fruit appear. A truss can become heavy suddenly, and a branch may need its own soft tie to prevent splitting. Avoid tying directly across a cluster of fruit. Lift fruit off soil where possible, but do not force stems into sharp angles just to make the plant look tidy.
Keep the base of each plant clear enough for watering and inspection. Water the soil, not the leaves, and mulch with garden compost or leaf mould while leaving a small gap around the stem. In a greenhouse or polytunnel, ventilate on warm days to reduce humidity. Remove only yellowing, damaged or soil-splashed lower leaves with clean secateurs; healthy foliage is needed to ripen fruit. As the main stem reaches the top of its support, either lower it carefully if your system allows, or pinch out the growing tip late in summer so existing fruit has time to mature.
At the end of the season, remove ties and supports gently. Compost healthy plant material, but dispose of badly diseased material through green waste where that is the local recommendation rather than placing it in a cool compost heap. Clean canes, clips and reusable ties before storing them dry. Note which support worked with each variety and whether wind, crop weight or spacing caused trouble. A simple sketch of your greenhouse or bed will help you position supports before planting next year. Early preparation is easier than rescuing a collapsing tomato in August.
Frequently asked questions
How tall should a tomato cane be?
Choose a cane that will be taller than the expected mature cordon plant once at least 30 cm is pushed into the ground. Exact height varies by variety and site. Bush tomatoes generally need shorter, wider support rather than a tall single cane.
Can bush tomatoes be tied to canes?
They can, but do not train them as one stem or remove their sideshoots. Use several short canes, a cage or a low framework to hold spreading fruiting branches clear of the soil. Tie loosely and add support as the plant becomes heavier.
When should I put tomato supports in?
Install supports at planting time or shortly afterwards. Doing so avoids piercing established roots and lets you guide stems from the beginning. It is particularly important outdoors, where a sudden windy spell can bend or break an unsupported young plant.
General guidance for UK home gardens and allotments. Conditions vary by region, soil and season; the RHS or a local garden centre can give site-specific advice. Page updated 19 Sep 2026.