CORVALLIS, Ore. — Gardeners hear it often: right plant, right place.
It’s a fundamental rule of gardening, said Heather Stoven, a horticulturist with the Oregon State University Extension Service, and it applies to houseplants just as much as outdoor ones.
“Make sure you buy for location,” Stoven said. “That will help solve many problems that can come down the road.”
Plants can decline quickly when placed in unsuitable sites. Environmental stress sets a plant up for problems with pests and diseases. Distress shows up as scorched or yellow foliage, leaf drop and, often, death. Keep plants healthy with appropriate light exposure, a sensible watering schedule and suitable temperatures, and insects and pathogens are less likely to attack.
Match plants to light
Figuring out light levels can be confusing. Directional clues help:
- South-facing windows get the most intense sun
- East- and west-facing exposures offer moderate light
- North-facing windows provide low light
Avoid placing leaves against cold glass and keep plants away from heating vents or fireplaces to prevent drafts and heat stress.
Water less in winter
In winter, water lightly only when the potting mix is dry. Check by inserting a finger into the soil to the second knuckle, or lift the pot — if it feels light, it needs water. Always use containers with drainage holes so excess water doesn’t collect and cause root rot. Overwatering kills more plants than underwatering, Stoven noted.
“There’s very little to do once a plant gets root rot,” she said. “Unless it’s a well-beloved plant, it could be better to put up the white flag.”
Fertilize lightly during active growth
Houseplants don’t need fertilizer from November through March when growth slows. The rest of the year, feed in moderation with a slow-release product (granules, tablets or stakes) that lasts two or three months, or use a liquid fertilizer every other week or as directed. Burned leaf tips or a white crust on the soil surface usually signal too much fertilizer.
Watch for pests — and prevent them
Indoor plants can get pests and diseases just like outdoor plants. Common culprits include:
- Aphids
- Mealybugs
- Mites
Aphids are tiny and often pale green, clustering on leaf undersides. Mealybugs have a white, cottony coating. Mites are hard to see without magnification; their feeding leaves fine speckling that can bronze or yellow foliage, and severe infestations may produce webbing.
If pests appear, prune off infested stems and leaves to slow the spread. Rinse plants thoroughly with water, including the undersides of leaves. Stoven generally doesn’t recommend most chemicals indoors, but horticultural oils or soaps are good options when used according to label directions. You can also dab pests with alcohol on a cotton swab and then rinse with water.
Prevention is best: Inspect plants carefully before purchase. If you move plants outside in summer, check them again before bringing them back indoors.
Houseplants for different light levels
- Low light: pothos*, snake plant*, lucky bamboo*
- Low to medium light: peace lily*, dracaena*
- Medium light: weeping fig/ficus*, African violet, Boston fern, dumb cane*
- Bright, indirect light: anthurium*, spider plant, palm, peperomia
- Bright light: schefflera*, rubber tree*, succulents, cacti
*If you have children or pets, skip plants marked with an asterisk; they can be toxic if chewed or ingested.
Previously titled Light exposure key for growing successful houseplants
