Growing Cacti and Other Succulents Indoors
I grew up in Phoenix, so I thought I’d had my fill of cactus. (Picture being a Girl Scout and taking camping trips in a desert filled with inhospitable plants covered with spines and barbs.) But this past year I’ve really gotten into growing cacti and succulents indoors. Maybe that’s partially due to the fact that the mere sight of them makes me think of warmth and vacations. If you’ve always wanted try growing houseplants but needed something incredibly easy to care for, these are the plants for you.
Before I jump into how to care for cacti and succulents, let me first explain what these plants are. Simply put, succulents are plants that are good at storing moisture in their stems, leaves and/or roots so they do well in hot, dry conditions. All cacti are succulents, but not all succulents are cacti. A few succulents you’ll probably recognize right away are jade (Crassula arborescens), aloe (Aloe barbadensis), flowering Kalanchoe (Kalanchoe blossfeldiana) and, of course, the Christmas cactus, which is both a cactus and a succulent. (FYI: Christmas cacti have very different needs than other cacti and succulents, so don’t go by what I say in this article when caring for them.)
Cacti and succulents are easy for beginning gardeners to grow because they don’t need much to thrive. As you might imagine, they don’t need a lot of water. In fact, the easiest way to kill these plants is overwatering. During the growing months, April through mid-September, you’ll want to water more often than in the winter when cacti, and most succulents, can usually get by with once-a-month waterings. If anything, it’s better to err on the side of dryness when it comes to cacti, which will shrivel and shrink a bit when they really get dry and need a drink.
Always grow cacti and succulents in pots with drainage holes in a soil mix that doesn’t hold moisture, such as equal parts of potting soil and coarse sand. Without good drainage these plants can easily become waterlogged and decay and rot. When you do water, I would suggest moving cacti and succulents to the sink where you can water thoroughly enough to see water flowing out the drainage holes. Be sure the pot is thoroughly drained before placing it back in a dish that could trap excess moisture.
Now that you know cacti and other succulents can do with very little water, you’ll be pleased to know they don’t need much food, either. Cacti will do just fine if you only fertilize them once a year in the summer or late spring when they’re actively growing. (Twice if you really want to.) Other succulents will generally do best if they’re fertilized up to four times during spring and summer. Choose a fertilizer that’s higher in phosphorous than nitrogen and then dilute it to about half the rate that’s recommended.
Cacti and succulents will do best when they’re grown in a sunny spot indoors but you can grow them in less optimal locations. I have several in north- and east-facing windows and they do just fine though I don’t get blooms and I have to be very careful with water since they don’t dry out as quickly as they would in the sun. (Do be careful in the heat of the summer that plants in sunny windows don’t burn.) And it’s not a bad idea to turn cacti and succulents from time to time so all sides of the plant get the sun they need.
Some cacti will flower fairly well indoors if they get enough sunlight and indoor temperatures are on the cool side at night (species of Lobivia, Mammillaria and Rebutia are good bloomers that are usually easy to find). When you’re shopping for cacti you’ll often see them in bloom but beware. Those blooms may be colored straw flowers stuck into the plant for show. So look closely at what you’re buying and if you’re in doubt, ask someone at the garden center for help.
One last thing, a lot of people like the look of several small cacti grouped together in a shallow dish filled with gravel. There’s nothing wrong with creating this kind of display (except that the sight of it would give me post-traumatic-Girl-Scouts-in-the-desert disorder). Just be sure that when you create your desert garden you choose plants that have the same water needs. For example, don’t put cacti with other succulents (generally speaking) because cacti usually require much less water than other succulents do. Also, try to choose cacti that will grow at about the same rate so some aren’t towering over others.
This post originally appeared in the Southwest Journal.