Small Bumps on Tomato Vines

Tomato Stem Primordia

• Bumps or tomato stem primordia located near the lower portion of the stem are where the plant created root initials. These root initials form at the lower part of the stem regardless of where the soil line is on the plant. Typically, root initials look green and have a bumpy appearance. If the root initials look discolored, your tomato vine may have contracted a disease. Tomato stem primordia located near the top portion of the stem also indicates health problems.

Problems

• Tomato stem primordia located at the top of the tomato stem indicates that your plant is suffering from excessive moisture in the soil, according to Washington State University. When the soil contains an excessive amount of moisture around your tomato vine, the plant creates more roots to absorb the water. While tomato stem primordia on the top regions of the vine doesn't harm the plant, it indicates that watering practices must be changed to prevent the plant from contracting root rot.

In Ground Watering

• Tomato plants generally need 1 inch of water a week. Provide 2 inches of water during the heat of the summer. One inch of water is 60 gallons per 100 square feet of garden space. To know how much rainfall your tomato plant has received, set out tuna cans in the yard. A tuna can is 2 inches in height. When the tuna can is halfway full, you do not need to apply water. However, tuna cans that are less than halfway full, means that you need to supplement water.

Container Watering

• Container grown tomato plants may produce tomato stem primordia if they are not placed on a saucer filled with gravel. Placing a container with drainage holes on the soil prevents adequate soil drainage. Containers must be set on saucers large enough to accommodate their size with half an inch of pea gravel at the bottom. The space between the pea gravel and container helps with drainage. When watering your tomato plant, lift the container so that the water flows from the drainage holes before placing it back on the saucer.