Light comes first
Watering gets the blame, but light sets the terms, because a plant in dim light uses water slowly and its soil stays wet. South-facing windows give the strongest light, east and west give moderate light, and north gives the least. Bright indirect light, the phrase on most plant tags, means within a few feet of a bright window but out of the direct beam. Low-light tolerant means the plant survives across the room from a window, not that it grows in a windowless bathroom.
How to water
When the top inch or two of soil is dry, water thoroughly until water runs out of the bottom, then empty the saucer after fifteen minutes. Small sips wet only the surface and leave the roots dry. The pot must have a drainage hole. If you like a decorative pot without one, keep the plant in its plastic nursery pot and set that inside. Plants drink less in winter, when growth slows, so stretch the interval. The symptoms point in different directions:
- Yellowing lower leaves, soft stems, soil that stays damp and tiny flies hovering over it all indicate too much water.
- Crisp brown edges, drooping leaves and dry soil shrinking away from the side of the pot indicate too little.
Repotting and feeding
Repot in spring, every year or two, when roots circle the inside of the pot or grow out of the drainage hole. Go up only one size, an inch or two wider, because a large pot holds more wet soil than the roots can use and they rot. Use bagged potting mix, never soil from the yard, which compacts and brings insects indoors. Feed with a balanced liquid fertilizer at half the label strength about once a month in spring and summer, and stop in winter.
Pests
Keep new plants apart from the others for two weeks. Fungus gnats signal wet soil, and letting the top inch dry out plus a yellow sticky trap ends them. Fine webbing under the leaves means spider mites, which a firm rinse in the shower and insecticidal soap will control. White cottony tufts are mealybugs, and a cotton swab dipped in rubbing alcohol removes them.
Note Pothos, snake plants and ZZ plants are all mildly toxic to cats and dogs that chew them, and true lilies can be fatal to cats. Check a veterinary poison list before bringing a plant home to a pet.
