Last Mother’s Day, our waiter delivered the check—and some bad news: The restaurant ran out of complimentary plants for moms. “That’s okay,” my 13-year-old retorted. “It would have died anyway.” That may have been blunt, but she was right. Dozens of innocent African violets, orchids, poinsettia, and other potted gifts have wilted under my care, or lack thereof. Of course, I offered water and light—but perhaps not enough or too much. How was I to know for sure? That’s why I consulted a couple of experts, who helped identify the problems and suggest a few simple solutions so that all of us black thumbs can start to slay at indoor gardening…or least keep the ferns in the hallway alive.
Not every species will work in every home. “You need to consider how much light the plant will get and whether you typically forget to water,” says Karl Gercens, a senior gardener at Longwood Gardens in Pennsylvania. Employees at garden centers—more so than supermarkets or home stores—can help guide you to the right plant for your conditions. If you’re buying a plant as a gift or are looking for something that’s practically foolproof, hone in on philodendrons, which are especially hardy. “I particularly like the newer varieties that have red, yellow, or orange foliage,” says Gercens. (And you should probably avoid fiddle-leaf figs...)
Aloe, cacti, Boston ferns, and euphorbia milii (crown of thorns) require a lot of light, so a cubicle or the corner of your living room isn’t the right place for them, notes Christian Primeau, conservatory manager at The New York Botanical Garden. On the flip side, monstera deliciosa (the Swiss Cheese plant), begonias, and epiphyllums (like jungle cactus) thrive in low-light or filtered-sun environments. If you’re not sure what your plant needs, look on houseplant databases like Tropicopia. Simply moving the plant to another spot in the house could work wonders.
“When a plant, even one that requires a lot of light, gets moved to direct sun after spending the last nine months indoors, it will burn quickly and easily,” says Gercens. “It might also start rotting if there’s been too much rainfall.” If you want to move your plants to the open air, make the transition gradually and keep tabs on moisture levels.
Since succulents and cactus plants prefer dry soil, watering daily will harm them. Once a week is plenty. “If you often forget to water or spend a lot of nights away from home, they’re a good choice,” says Gercens. Another option: zamioculcas (nicknamed the ZZ plant), which only require water once every two weeks or so. “My wife grows the ZZ plant in her cube at work with no natural light and minimal watering,” says Primeau. (Check out this list of 10 houseplants you hardly ever have to water.)
Plants that are blooming require watering more often than when they’re in a dormant period. As a general rule, check the soil and tips of the leaves to see whether they’re dry, indicating that the plant needs water.
Here’s another useful tip: When you water plants, be careful not to get droplets on the leaves; this promotes fungal growth. (I believe this is what led to the undoing of my African violets.) If you have an Android phone, download the free Waterbot app, which will send you reminder notifications when it’s time to water.
Spider mites, mealybugs, and scale insects prey on your household plants. Primeau’s favorite organic pest control that’s especially effective on mites and mealybugs: neem oil concentrate. “You mix it in a spray bottle with water and spritz it on your plants every one to two days,” he says. “It smells like citrus.” Neem oil compounds will repel some insects by disrupting their reproductive or developmental cycles. It also deters some insects from feeding on foliage.
Plastic pots tend to retain moisture, so they’re best for plants that like a lot of water. Clay pots, on the other hand, are the perfect choice for plants that prefer drier conditions, like cacti, orchids, and succulents. Since they’re porous, clay pots can’t hold onto as much water. Also, consider the size of the pot. “Don’t choose a pot thinking that the plant will grow into it,” says Primeau. “Chances are good that the plant will take in too much moisture with all that extra room in the pot.” When you’re transplanting, select a pot that’s 2 to 4 inches larger in diameter than your current one.
Dirt from your yard and packaged topsoil aren’t the best choices for growing houseplants. Instead, you want an indoor potting mix that is loose enough to allow the roots to grow easily, but not so loose that the water just runs right through to the bottom. You can purchase mixes specifically for the type of plant you’re growing (just ask someone at the garden center if you’re not sure what mix to choose), and there are many organic choices available, too. Then swap the soil every year or two.