Greenhouse Tomatoes

Why do the plants get flowers, but don't get fruit?

This can really cut into sales. There are several possibilities here. Any kind of stress on the flower can prevent fruit set. These include 1) temperature is too high: getting much higher than 90º F is approaching the danger zone; 2) temperature too low; 3) drought stress - i.e. if the plants are wilting; 4) using too much nitrogen - this often creates very healthy, lush, dark green plants, but few flowers or fruit; 5) salt stress - if the EC in the root zone is too high. Other than stress conditions, it is important that flowers be pollinated every other day to get good fruit set.