FLORIDA — Each spring, gardeners submit questions about the pollination of vegetable crops. Plant pollination is the transfer of pollen from the anther (male part of the flower) to the stigma (female part). Following pollination, fertilization must then occur through the union of male and female cells.
Though this process goes mostly unseen, it is necessary for fruit development in most cases.
Here are some of the pollination questions with answers:
Q. If I plant two varieties of the same vegetable near each other in the garden, will the resulting fruit be a mixture of these two varieties?
A. No, the resulting vegetable should have the characteristics of the original variety planted during the first generation from seed. The result of cross-pollination would only begin showing up if you saved seeds and produced plants from them in the future.
However, there are exceptions. Sweet corn, when fertilized with pollen from a different variety, can result in color and flavor differences. Also, if you plant sweet and hot peppers near each other, you might harvest sweet peppers that are also hot.
Q. I would like to plant both white and yellow sweet corn. How can I prevent the two varieties from mixing/crossing?
A. This can be accomplished by separating the two planting dates or the distance between plantings. Sweet corn is wind pollinated, so if planted simultaneously, the two varieties should be at least 300 feet apart. Planting at least two weeks apart should also be sufficient to avoid cross-pollination.
Q. My cucumber, squash, and watermelon won’t set fruit even though the plants appear healthy. What am I doing wrong?
A. This is probably due to a lack of pollination. Cucurbit crops, cucumbers, squash, and melons, have separate male and female flowers on the same plant but in different locations. These crops rely on insects such as honeybees to move the pollen from the male to the female flowers.
The lack of bees can result in poor pollination and subsequently lack of fruit production. It takes approximately eight flower visits by bees to produce a well-developed fruit. New flowers open each morning, and bees are most active shortly after sunrise until mid-morning.
You can try hand-pollinating a few plants. This can be done by transferring pollen from newly opened male flowers using a small brush. Deposit it on the stigma, which is on a raised area in the middle of the female cucurbit flower.
Here are links to two Extension publications with more info on pollination, including hand pollination:
- https://edis.ifas.ufl.edu/publication/HS398
- https://secure.caes.uga.edu/extension/publications/files/pdf/C%20934_5.PDF
Larry Williams is the Extension horticulture agent with the Okaloosa County Cooperative Extension Service, University of Florida. Contact Larry at 689-5850 or email lwilliams@myokaloosa.com.
