The female parts of all plant flowers need male pollen so they can bear fruit. Lime trees are self-fruitful, meaning their flowers contain both male and female parts, so they provide their own pollen. You can grow Mexican limes (Citrus aurantifolia) or Tahitian limes (C. latifolia) outdoors in U.S. Department of Agriculture plant hardiness zones 9 through 11. If you grow a lime tree outdoors, bees and other pollinating insects will transfer the pollen from the male to female parts. If you grow a dwarf variety indoors, you have to transfer the pollen by hand.
Lime Flower Parts
The sticky female stigma is located in the center of the lime flower. The stigma will develop into limes once it receives pollen. The stigma is surrounded by the male parts, called anthers, long filaments that have fluffy yellow grains of pollen on their ends. The transfer of pollen from anther to stigma is called pollination.
You do not have to plant two lime trees together for the flowers to be pollinated outdoors; however, you do need foraging bees or other pollinating insects. The bright color of the flowers attracts the bees that feed on the sweet nectar inside. When a bee bumps against an anther containing male pollen, the pollen sticks to the tiny hairs on its body. When the bee touches the sticky female pistil, the pollen is transferred and the flower can begin growing a lime. The more bees you have, the more flowers are pollinated and the more limes your tree will yield.
Pollinating Indoor Limes
You can grow dwarf varieties of the Mexican lime indoors. Dwarf varieties of Mexican limes, also called key limes, grow to about 2 feet tall. This is the smooth, green lime that you typically find in supermarkets. If you grow a lime tree indoors or if you grow it outdoors but have no bees, you have to pollinate it by hand.
Pollinating Lime Flowers by Hand
To pollinate a lime flower by hand, you have to transfer pollen from the male anthers to the sticky female stigma. To do this, gather some yellow pollen with the tip of your finger, a cotton swab or a small, soft paintbrush. Gently transfer some of the pollen onto the stigma, making sure some of the pollen stays in place. Repeat this process for each flower that you want to grow a lime.
Your Planting Articles
- Zedcor Wholly Owned/PhotoObjects.net/Getty Images