How to Prune Indeterminate Tomato Plants

Carefully pruning an indeterminate tomato plant will make it more productive.

Indeterminate tomato plants, unlike determinate tomato plants, will grow and produce tomatoes all season long. As these tomato plants grow they develop what are called suckers, which grow into weak side stems. These undesirable shoots sap energy from the plant and the fruit will be smaller and weaker. Suckers can also cause the plants to become unwieldy and fall over. Controlling these shoots is not hard and leaving a few strong offshoots will make the plant yield more tomatoes. Stay vigilant about pruning suckers from indeterminate tomato plants and the plant will produce well all summer long.

Things You'll Need

• Sharp knife

Instructions

1. Look for suckers. These offshoots first appear as small shoots where the main stem joins the leaf stem. Suckers first appear at the stems near the bottom of the plant and eventually grow all along the main stem.

2. Decide which suckers to remove. The shoots lowest on the plant will be the strongest, so choose two or three of them and allow them to continue growing.

3. Remove suckers from sections where a leaf stem joins with the main stem. Use your thumb and forefinger to pinch the sucker off at its base, where it emerges from the joint. If the offshoot is too large and hard to pinch off use a sharp knife to cut it.

4. Remove any other branches that crowd the plant. Cut them off with the knife. Make sure light and air can get to the middle of the plant but don't cut off so much that the plant is weakened.

5. Check the tomato plants for new suckers every few days and remove them before they get large.

Tips & Warnings

• Avoid using knife or pruning shears as the larger cut could cause infection. Check often.

References

• Fine Gardening: Pruning Tomatoes