How to Care for a Cactus

Cacti make great houseplants. They’re easy to grow because they’re tough desert dwellers that need little help from you to be healthy. No contemporary, eclectic or midcentury mod decor right now is complete without a potted cactus playing the role of living sculpture, so they’ve replaced fiddle leaf figs as the must-have houseplant. To keep a cactus happy and healthy, you must give it the right conditions, the ones it would get in its native desert. Here’s how to make a cactus thrive indoors.

Light

A cactus needs a ton of sun. Most varieties need at least eight hours of direct sun a day. Place them by a southern window or beneath a skylight for maximum sun time. Move them outside in the spring and summer so they can bask in 10 to 12 hours of real, unadulterated sun.

Temperature

In the spring and summer, when they’re in their active growth period, cacti like hot temperatures ranging from 70 degrees to 95+ degrees. In the winter, when they’re dormant, they like cooler temperatures, down to 55 degrees. Some cold-hardy cacti can withstand freezing weather.

Water

Cacti need more water in the spring and summer when they’re doing most of their growing and blooming. Water them whenever the soil is bone dry. In the winter, when they’re dormant, don’t water them unless they begin to shrivel. They’re asleep, so leave them alone. You may only need to water them two or three times for the entire season.

How you water them is as important as how much you water them. There’s not much rain in their native deserts, but when it rains, it pours. We’re talking sheets of rain. Imitate those desert monsoons by drenching your cactus in water. Periodic deep soakings are better than frequent light waterings. Just be sure to let the soil dry out completely before you water again.

Soil

A cactus needs well-drained soil, so don’t plant it in standard potting mix. Buy a soil mix made just for cacti, or mix up your own by adding one part perlite or pumice to one part standard potting mix. Standard potting soil holds too much water and can cause a cactus to rot at its base.

Repotting

Cacti grow slowly, so you won’t have to repot often. Unlike other plants that should be repotted annually, a cactus can grow happily for years in the same pot. Remember, many species of cactus will bloom more if they’re in a pot that’s a little too small. Cramped roots stress the plant just enough to make it bloom.

Fertilizer

Feed plants only during the growing season, spring and summer. Cacti like acidic conditions, so use a specialty fertilizer.

Common Problems

• Overwatering, especially in the winter, is the mistake cactus owners make. Too much water will rot the base or tips of the plant. Remember, don’t water it in the winter unless it starts to shrivel. In the summer and spring, when the plant is growing and needs water, let the soil get bone dry before you water it again.
• Pests like mealybugs and mites can infest cactus, especially if you overwater them.