Backyard gardeners are fretting these days about their long-awaited favorite summer crop, the tomato. Some are waiting for those green orbs to turn into the first juicy, red "love apple" of the season. Other vegetable growers would be happy to see any sort of fruiting action on their bare tomato vines.
Dennis e-mails us with a typical tomato concern this time of year:
"I've got five tomato plants, and they are all doing very well, except that I have noticed that on at least a couple of them the flowers have fallen off. Does that sound like a pest to you or possibly a watering issue?"
Tomato blossom drop is fairly common in mid to late spring. Sometimes it's because the weather isn't cooperating. If it's too cool (night time temperatures below 50 degrees) or too hot (daytime highs over 90), those young tomato flowers will fall. This situation should rectify itself.
But there can be other factors as to why those tomato blossoms are falling, according to Gary Hickman, University of California Horticulture Advisor.
"One common problem is the overuse of nitrogen fertilizer, " says Hickman. "This plant nutrient keeps the vine vigorous and a nice dark green color. However, when in the vegetative part of its growth, the tomato plant does not produce flowers and therefore no fruit. The simple solution is to cut back on the nitrogen and flowering should follow."
Another common mistake of some gardeners is to plant the garden in too much shade. "Since most producing vegetable plants do best in full, day-long sun, anything less will often result in less fruits and vegetables," advises Hickman. "Remember that a plant in the sun will probably need more water than one grown in the shade. This does not mean to water more often, but to water more deeply when you do irrigate. This will help prevent a water stress to the plant, another common reason for a poor tomato crop."
There are several commercial hormone sprays available to improve tomato fruit set. However, if the problem is high daytime temperatures, even these sprays will not help. All you can do is wait and hope that the weather cools.