How to keep your houseplants pest-free

The best way to protect your houseplants from thrips, spider mites, mealy bugs and other pests is to make sure you care for the plants properly.

If a plant is struggling, assess its cultivation needs: Does it need full sun or filtered light? Does it thrive in warmth and prefer humidity? Is the soil too dense? Are you watering it enough? Or too little? Does it need to be fed with a liquid fertilizer? Or have you given it too much?

Improper care can weaken your houseplants and make them susceptible to pests that travel indoors on your newspaper, pets, newly purchased plants or potting soil.

Be sure to check your plants for insects before bringing them home, and wash planters before repotting your plants. Even though insects are tiny, try to check roots, stems and leaves when you transplant your houseplants. If you take your plants outdoors to water them or to enjoy the rain, check for pests before you bring them inside.

L.A. County master gardener Julie Strnad advises growers to keep their plants clean. "It may involve taking them to the kitchen sink and washing them and wiping the dust off their leaves," she said. "Don't ever buy a plant that doesn't look clean and healthy."

Humidity is another factor in attracting insects. "Our homes are hot and dry, and there is not always good air circulation," said Strnad. "That attracts insects. Spider mites are very common in the winter because they love hot, dry air."

It's easy to add moisture by misting or by using a humidity tray (pebbles and water in a tray or saucer) underneath plants, but be sure to clean the pebbles before bringing them into the house. "That's a good way to bring pests indoors," Strnad said.

If you do find pests, Strnad advised washing them off with water and a little dish soap.

"When you ignore things, especially in hot, dry air in the house, you set yourself up for pests," Strnad said.