Technique for Self-Pollinating Plants for Abundant Crop Yield
In the world of fruit-bearing plants, sometimes natural pollinators can't do their job, or you might be growing these delightful plants indoors. When this happens, hand-pollination becomes a go-to solution for a bountiful harvest. Here's a simple guide on how to hand-pollinate your plants, ensuring successful fruit development.
We've asked two experts to lend us their green thumbs—Susan K. Brown, an apple breeder and professor at Cornell AgriTech, and Madeline Oravec, assistant professor of grapevine breeding at Cornell AgriTech.
When to Take Matters into Your Own Hands
Typically, nature does a swell job with pollination, but there are scenarios where human assistance is called for—greenhouse cultivation, high tunnel farming, indoor gardening, or simply a lack of bees, butterflies, or hummingbirds. Gardeners also resort to hand-pollination for breeding new varieties or guaranteeing pure seeds for saving.
Self-Pollination vs. Cross-Pollination
Plants can either self-pollinate or cross-pollinate, and it's crucial to understand the differences.
Self-Pollination
Self-pollination happens when a plant pollinates itself. Tomatoes, for example, self-pollinate when pollen travels from the anther (male part) to the stigma (female part) of the same flower. These plants have both male and female parts in the same flower.
Cross-Pollination
Cross-pollination is the process of transferring pollen from one plant to another. Apples, for instance, require cross-pollination through wind or bees. Cross-pollinating plants often have vibrant colors, strong scents, and nectar to entice pollinators.
Hand-Pollinating a Self-Pollinating Plant
Hand-pollinating a self-pollinating plant involves transferring pollen from the anther to the stigma. To do this, select a male flower and brush it against the stigma. The sticky stigma will show signs of pollen. You can also brush the inside of the flower with a small paintbrush, ensuring the pollen finds its way down into the pistil (the central part of the flower).
Hand-Pollinating a Cross-Pollinating Plant
For a cross-pollinating plant, you'll need to move pollen from one plant to another.
- Identify a mature, opened female flower with a wet and sticky stigma at its center.
- Choose a healthy, pollen-rich male flower.
- Use tweezers to remove the anthers and place them in a small dish or test tube.
- With a clean paintbrush, gently paint the pollen from the dish or tube onto the stigma of the female flower. You should see yellow pollen on the stigma's tip.
Remember to tag the pollinated flowers to track progress.
Best Practices for Hand-Pollination
- For self-compatible or poor pollen shedding plants, consider using a "pollinizer" variety.
- Plants with separate male and female flowers (such as squash) can be hand-pollinated by identifying the swollen female flower base.
- If you're breeding plants, gently remove all the anthers before the pollen matures to ensure only the intended pollen reaches the stigma.
- Use an oscillating fan for indoor plants or gently shake or tap the stem below the blossoms to aid self-pollination.
Embrace the green-fingered life and let hand-pollination boost your fruit-bearing plant production!
Martha Stewart suggests that growing apple trees indoors may require hand-pollination for successful fruit development due to a lack of natural pollinators. To hand-pollinate an apple tree, one might require a credit line to purchase a small paintbrush, as the process involves transferring pollen from a pollen-rich male flower to the stigma of a mature, opened female flower. For best results, it is recommended to identify and remove all anthers before the pollen matures on plants with separate male and female flowers, such as squash.
