WikiGardener
Advertisement

A tomato stem showing enlarged primordia

Tomato stem primordia are tiny bumps that may appear on the stem of a tomato plant. They are the beginning of a new root node which will develop when in the presence of water or if the plant should lose contact with its existing root system.

Symptoms[]

Small stipples appear along the stem of the plant. There may only be a few small patches or it might cover the majority of the stem.

Treatment[]

None. This is usually nothing to worry about. The development of primordium is usually caused by high humidity, sustained wet weather or overwatering.[1] Primordia are critical to the proper positioning and development of plant organs, in this case the root system. Advice on planting tomatoes often includes burying a proportion of the stem when potting on as this promotes the primordia to develop.

Bumps can, however, be a sign of a problem with the root system. Provided that the plants are not overwatered; continue to monitor any further growth.

Prevention[]

Ensure the plants are not kept in excessively humid or wet conditions.

References[]

Advertisement