Doin’ the Pollinate Shake!
How to hand pollinate plants in the vegetable garden.
No, it’s not the latest dance craze. It’s what certain plants in your vegetable garden need to set fruit: a good shaking. Yes, it has to do with sex, er, pollination and plants can sometimes use a little help. But what it really has to do with is better yields come harvest time. So let’s get ready to pollinate!
Not a year goes by when we don’t hear someone complain that their tomatoes, cucumbers, or squash didn’t set fruit. Oh, the plants grew like crazy and blossomed to beat the band but when it came time to produce? Little or no fruiting occurred. We’ve even had this happen ourselves, usually after relocating to a different part of the country. When we’re asked what went wrong, we realize (doh!) that we didn’t do what needed to be done, that’s when we remember hand pollination. Now that July has arrived and gardens around the country are beginning to flower, it’s time to pollinate. (For those of you in cooler climates or whose gardens might be a bit behind schedule this year, here’s hoping that your blossoms are soon to show.)
What’s hand pollination? It’s the process of helping Mother Nature along in her attempts to bring fruits, even if those fruits are vegetables (see Bees & Butterflies Battling Demise). Tomatoes, peppers, egg plants, cucumbers, melons, and the like often need some help from you. Let’s start with tomatoes.
Tomatoes are self-pollinators. Each blossom contains all it needs to produce fruit — it has both male and female parts. Usually a bit of wind or a visit from a pollinator is all it needs. But often in sheltered gardens or places where pollinators are low in numbers because of nearby spraying or other reasons tomatoes will need our help. A gentle shaking is sometimes all that’s needed. Shaking the plants allows the pollen to drop and intermingle. Best time to do this is at midday when temperatures are warm and the humidity is low. Peppers and eggplant will also respond to a gentle shaking. Or you can disturb the inside of the blossom — gently, gently — with your finger or a thin brush.
After growing tomatoes successfully in the Midwest and the cool climes of the Pacific Northwest, I eagerly looked forward to a bountiful harvest after a move to coastal California. My little patch was sheltered by fences, trees and hedges and that first year we gathered only cherry tomatoes from a plant by the sidewalk. None of the other plants produced. A neighbor suggested that all we needed to do was shake our tomato plants when they blossomed. He thought our cherry tomato yielded well because it was brushed as we walked by it. Another neighbor said she used an electric toothbrush to gently vibrate her plants. We didn’t go that far but the next year we made sure to shake our plants when they blossomed (and then there was that earthquake). Anyway, we had tomatoes galore.
Cucumbers require a little more attention. They have different male and female blossoms, though both will appear on the same plant. Learning to tell the difference isn’t hard. The male blossoms will often grow in clusters, the female blossoms singly. Male blossoms are usually the first to appear. Female blossoms will begin at a small fruit, the characteristic that makes them easiest to identify.
To hand pollinate, remove the petals from a male blossom to reveal the stamen at its center. If you look closely, you’ll see pollen clinging to it. Touch it with your finger or a small paintbrush and carry the pollen on your finger or the brush to the female blossoms. Touch them at their center. Be sure to refresh your brush with pollen every few touches. This can be a tedious process but it’s worth it, especially if you haven’t had many cukes in previous years. The same technique works for squash and melons. It’s actually easier to do with them because the parts of its blossoms are larger. Here are some photos an instructions that will help you identify male and female blossoms.
Of course, many gardeners have no problem with natural pollination. But with declining numbers of bees, fruit-setting problems are on the rise. Sometimes adverse conditions, especially high night time temperatures will keep your tomatoes, cucumbers and other vegetables from setting fruit. Not much you can do about that (that I know of, anyway). More information on problems with pollination can be found on this release from Washington State University extension (PDF).