Houseplants are good for what ails our homes. Beyond being decorative, they purify the air we breathe by producing oxygen while reducing harmful indoor pollutants, including formaldehyde, benzene, carbon monoxide and nitrous oxide.
But unfortunately, many plants suffer from indoor sicknesses caused by misguided humans who don’t know their proper care and feeding. The biggest mistake — “not giving consistent care,” says Maritza Padgett. She ought to know. Along with husband Wayne, they are founders and owners of Plant People Inc., a San Diego business specializing in care of indoor plants in restaurants, office buildings, hotels and homes. Maritza Padgett estimates that she and her staff have tended hundreds of thousands of indoor plants since establishing their business in 2000.
The most common mistakes to avoid:
•Lack of cleanliness. Indoor plants need to be dusted or cleaned regularly, preferably once a month. Padgett does not recommend a leaf-shining product, because it can coat leaves so they aren’t able to transpire (take in carbon dioxide and other gases and emit oxygen). Instead, a few drops of mild dish soap (not detergent) in a pint spray bottle, sprayed and then wiped off leaves, removes dust and grime. Plants in small containers can be rinsed in a sink or shower.
•The wrong amount of watering. Conventional wisdom is to water only if soil 1 inch below the surface is dry. But Padgett disagrees with this approach. “Don’t water unless roots are dry,” she recommends. “Use a soil probe or crochet hook, insert straight down and remove a small soil sample near the root zone. If this is wet, don’t water.”
•Wrong placement. Plants need some amount of natural sunlight. Consider where you want to put plants and check how much natural light is present. Do some research and choose plants appropriate for low, moderate or high light conditions.
•Poor drainage. If pots don’t drain well, plants can suffocate from excess water in the root zones. If your favorite pretty pot doesn’t have drainage holes, add them yourself.
Here’s what to do
•Water according to each plant’s needs. Probe soil to determine when. Padgett discourages moisture meters. “Unfortunately, they’re not as accurate as checking the soil yourself.”
•Add humidity. Indoor plants, especially in winter, can suffer in warm, dry rooms. Some plants respond to misting. But plants with hairy leaves like African Violets, don’t. These types of plants can be placed on shallow trays with a thin layer of decorative gravel or pebbles to retain water and humidity.
•Fertilize during growing seasons, spring through fall, with a water-soluble fertilizer. Follow product directions and, in general, apply every two to four weeks.
•Repot plants as needed. Use sterile mix, not outdoor potting soil, to avoid infestations of fungus gnats. When repotting, be sure to pick proper size. “Plants should be moved only one size up, Padgett said. “A plant in a 6-inch container should only go into an 8-inch container. Any larger means there will be watering problems.” If you want to use the same decorative pot, root pruning will fix the problem. Remove plant, cut root ball back, replace old potting soil with new, sterile mix, and replant. Add water, but don’t fertilize until growth resumes. Root pruning or repotting can be done every two to three years, depending on plants.
•Don’t mix plants. They look so cute — those bundles of plants decoratively arranged in a pretty container. But they won’t grow and thrive because roots will compete. Padgett recommends removing all plants and repotting them into individual containers.
•Control insect pests. Spider mites, mealy bugs, aphids and fungus gnats are pests that can attack indoor plants. Remedies include spraying with appropriate, nontoxic products, including oil or soap, swabbing with alcohol and putting commercial sticky traps into infested pot. As with any plant, early detection is key to control.