Tomato plants but no fruit? - East Idaho News
In the Garden

Tomato plants but no fruit?

  Published at  | Updated at
Getting your Trinity Audio player ready ...

PRESTON — Do you have healthy tomato plants but lack tomatoes on the vines? You may have heard advice from neighbors telling you to prune back the vines or to stop watering to solve the problem. Do not be discouraged, just read on!

If you are getting flowers but no fruit, it is likely due to not enough water or simply that it’s too hot. Drought stress in tomato plants can cause flowers to wither or drop prematurely. Tomato plants have flowers that contain both male and female parts within the same flower. The tomato flowers hang down in a cluster and are pollinated when shaken by movement such as wind. When the flowers are not properly pollinated, they drop off, and no fruit develops.

Unfavorable weather conditions are the primary reason for blossom drop on tomatoes. High daytime temperatures (above 90-95 degrees Fahrenheit) or low nighttime temperatures (below 50 degrees Fahrenheit) interfere with pollination, causing blossom drop. Several days of nighttime temperatures above 70 degrees Fahrenheit may also cause the plants to abort flowers. When it’s too hot the pollen becomes nonviable, preventing pollination from taking place. Strong winds and dry soil conditions may also contribute to blossom drop. Strong winds desiccate flowers, while dry soil conditions stress tomato plants. With continued high temperatures, the best thing you can do is keep the plants irrigated. Fruit set should increase when temperatures moderate.

Remember, with tomatoes it is best to water at the base of the plant or at least to water early in the day so the plant does not have water on the leaves at night. Water tomatoes deeply and infrequently, applying 1-2 inches per week. Mulch around the plants will help conserve soil moisture and reduce weed growth. Over or under-irrigating can cause blossom-end rot, a dark leathery spot on the bottom of the fruit.

Also, care must be taken to avoid using too much nitrogen fertilizer. Nitrogen mainly promotes green growth. If tomato plants have too much nitrogen, they will continue putting energy into growing more vines and leaves at the expense of blossom and fruit production. At this point in the growing season, if you have green healthy tomato plants, don’t add more nitrogen fertilizer. This adjustment will encourage plants to shift towards fruit production.

SUBMIT A CORRECTION