Vegetable Gardens & Cross Pollination Problems

Cross-pollination only occurs between plant varieties not plant species.

Pollination is an important natural process that is crucial to vegetable production. Some vegetables are wind pollinated while others are insect pollinated. Cross-pollination occurs when the pollen from one vegetable pollinates a different variety. Cross-pollination will not occur between different vegetables and will only cause a problem if the gardener is going to save seed from one year to the next.

Cross-pollination Process

Cross-pollination can occur when insects visit different flowers in the garden. It can also occur when the wind blows or can be performed by a human through hand pollination.

Preventing Cross-pollination

Cross-pollination can be prevented in many ways. One way is to plant only one vegetable variety for each desired vegetable. This means only planting summer squash instead of summer squash and acorn squash. Another approach is to hand pollinate those plants that have a tendency to cross-pollinate.

Hand Pollination

Hand pollination is a way of preventing cross-pollination but the gardener needs to be diligent in this approach. Once blooms begin to appear on plants in the gourd family, monitor the situation until both male and female blooms are present. To identify the difference, keep in mind that the male flower is smaller than the female flower. To perform the hand pollination, take the anther of the male flower and brush it with a paintbrush to pick up the pollen. Then transfer the pollen to the stigma of the female flower and tie the top of the bloom off. Corn can also be hand pollinated. The male flower or tassel is located at the top of the plant. The female flower or silk is located farther down on the stalk above the leaves and at the nodes or joint of plant. There does exist two ways of pollinating corn. The first approach is to cut the tassel off and wave it over the silks like a wand. The other approach is to strip the tassel down to the anther and apply the pollen directly to the silks.

Cross-pollinating Plants

Plants that are Cucurbitaceae or in the Gourd family are notorious cross-pollinators. This includes summer squash, Halloween pumpkins, vegetable spaghetti, acorn squash and small ornamental gourds. Another plant that cross-pollinates is the Gramineae family or corn. Pollination between the same variety produces corn that is edible and uniform in appearance to that variety. Cross-pollination of corn can cause it to not produce kernels that are true to the variety and in some situations make the corn inedible.

References

• University Of Illinois Extension; Common Vegetable Gardening Questions; Sandra Mason; July 24, 2006
• Mississippi State University Extension Service; Vegetable Gardening In Mississippi Pollination
• University Of Florida Extension; Home Vegetable Garden Techniques: Hand Pollination Of Squash And Corn In Small Gardens; Ed Thralls And Danielle Treadwell