Zucchini Not Producing

A customer came into the store last week, concerned that she wasn’t getting any zucchini from her summer squash plants. “I think I have all male flowers,” she said. Although it does occasionally happen that a summer squash will produce all or mostly male blooms, if you have more than one plant it’s unlikely that this is the reason for the lack of production. It would be very, very rare to have two or more plants that are producing only male flowers. Here are some of the most common reasons that squash plants don’t produce fruit:

1. Lack of pollinators. Be sure you have a variety of flowers around your veggie garden that attract bees and other pollinators to your garden. Zinnias, Nepeta, Echinacea and Calamintha are some of the plants that will bring in the bees.

2. Watering every morning. If you have a sprinkler that comes on in the morning, you’ll be keeping the bees away at the time when most pollination takes place. It’s better to water less frequently anyway, and watering with soaker hoses is also a smart way to irrigate. If you’re using a sprinkler, water deeply every five days so that on the other mornings the bees have access to your squash flowers.

3. Avoid insecticides. Needless to say, if you’re spraying an insecticide that kills all insects you’ll be doing in the very pollinators that will help you have fruit.

4. Rotting fruit. Keep developing fruit away from soil and again, avoid frequent watering. Sometimes there are female blooms that are getting pollinated but because the plants are getting watered daily the young squash rots before it develops. See photo below. Mulching under the plants to keep the squash off the soil, and watering less frequently so that the surface area around the plants dries up, will help prevent rot.

5. Young plants. Young squash plants often produce male flowers for a week or or more before they start to make female flowers. The guys are just anxious to get things going, I guess… patience usually ends up paying off, however, and the female flowers appear as the plants get older.

Male flowers have long stems with no swelling under the blossom. If you like stuffed squash flowers, pick the males after noon and cook them for dinnner.

See how the stem under this bloom is thick? This is a female flower that has been pollinated. To the right of the yellow bloom is another feamle that hasn’t opened and been pollenated yet. If that flower isn’t pollenated when it opens the swelling underneath won’t go on to develop into a summer zucchini. That’s why you want to be sure that the bees are on the job!

This is an example of a pollinated flower that started to make fruit, and the squash began to rot before it could develop. This plant is mulched with chopped leaves, but was watered in the AM on a particularly cloudy, humid day so the fruit stayed so damp that rot  set in.