By ANGELA O’CALLAGHAN
Now that it is summer, many of the local cacti have finished their astounding display of white, yellow, red, pink and purple flowers. Some of them produce a plant part that does not look like a prickly pear pad or a standard cactus where the flower had been. Just like other plants, these are the fruits.
Non-desert folks are often astounded that such a thing as a cactus flower even exists, much less, that such a spiny plant could create something as unexpected as a fruit. When they hear that many of these fruits are edible, it boggles their minds.
Just like any other plants, cacti need to reproduce, and just like other plants, they create seeds within those fruits.
If you open up a ripe cactus fruit, you will probably see a multitude of seeds. It makes sense that a desert plant would have such a large number, given that their growing conditions are so harsh. Only a very small number have a chance of growing to maturity in the Mojave, or any other desert. Lack of water or soil fertility cuts their rate of survival very low.
An intrepid desert gardener can try growing his or her own cacti from seed, although as you might imagine, this is a long, slow process. In the wild, the amount of natural resources available to the developing plant is small; it would not be wise for it to grow faster than the environment will support.
It is worth trying, whether you have youngsters you would like to engage, or you enjoy a challenge.
First, let the cactus fruit ripen to maturity – almost to the point of splitting open. Carefully remove the fruit. Kitchen tongs are useful to save fingers from the spines. Gently scrape the seeds out and let them dry on paper towels.
The soil needs to be fresh and disease free. If you plan to reuse some, make sure that you have sterilized it. Otherwise, purchase cactus soil and amend it with perlite for best drainage. The pots you use are your own choice, as long as they are clean and have holes so any excess water drains away easily.
Place the seeds on top of the moistened soil, and keep the pots under lights. Unlike many other plants, cactus seeds need light to germinate.
There are many opinions about the next steps. Many experts recommend watering the pots from the bottom, but never letting them sit in water. Others suggest using a plant heating tray (not to be confused with a heating pad, which would be a terrible idea.) The plant tray is pad that raises the soil temperature just a few degrees.
You may put the pots in closed plastic bags, opening them occasionally to avoid developing mold. That would be a sure death for any seedling but especially a desert plant. It may take three weeks or more, but once the seeds have germinated, remove them from the bag, add a little more sandy soil and keep them under lights.
Dr. Angela O’Callaghan is the Social Horticulture Specialist for University of Nevada Cooperative Extension. Contact ocallaghana@unce.unr.edu or 702-257-5581.
