Home & Garden

Well-cared-for indoor plants can do more than fill a space. Here’s what to do

A Peace Lily plant in an atrium.
A Peace Lily plant in an atrium. File photo

In the Central Valley we are forced by intense summer heat and unhealthy air quality to spend most of our summer days and nights inside, windows shut and air conditioning on full blast. We can find some relief from high temperatures indoors, but surprisingly we won’t find relief from air pollution. The air inside our homes and offices is can be more polluted than the outside air, perhaps two to five times more polluted according to federal estimates.

Elinor Teague

Major sources of indoor air pollution include VOCs or volatile organic compounds, building and paint products, carpets, cleaning supplies, plastics, formaldehyde, pet dander, dust and dust mites and fire retardant chemicals. Symptoms of indoor air pollution can resemble a slight cold or allergy and/or a fuzzy memory and difficulty in concentration which are alleviated by leaving the polluted environment. Long-term health conditions as a result of indoor air pollution have been studied and confirmed.

Houseplants have proven to be excellent filters for many common chemical pollutants. Some of those listed below are credited with absorbing up to 90 percent of benzenes, toluene, formaldehyde and acetone. Houseplants also release oxygen at night, increasing oxygen levels indoors when the windows are closed as they often are on hot summer nights.

Here’s five commonly available houseplants which are most efficient as pollution filters. An online search for “houseplants- air pollution’ will bring up more comprehensive lists. The excellent book “What Houseplant Where” from DK Publishing also provides good descriptions of beneficial houseplants.

Peace lily or Spathiphyllum – Tolerates warm temperatures and low light but does best and will flower in bright, indirect light. Water when top of the soil is dry.

Schefflera – Easy-care foliage plant. Variegated-leaf varieties are very attractive. Needs bright to moderate light and watering when the soil is dry.

Ficus – Both weeping fig (Ficus benjamina) and the rubber plant (Ficus elastica) need bright light, but no direct sun and warm temperatures. Water when soil dry, less often in winter when temperatures are lower.

Spider plant – A 1970s favorite hanging plant. Easy to grow and propagate. Takes bright, indirect light. Keep soil slightly moist, except in winter.

Jade plant – An easy-care succulent. When kept in bright light with morning sun it will flower in autumn. Water when the soil surface is dry, cut back on watering in winter.

If you can’t see the shadow of your hand on the wall, light levels are too low to grow houseplants. Bright, indirect light is best for most houseplants. Use shades or sheer curtains on south- and west-facing windows to prevent leaf burn. Move houseplants to brighter areas as the sun’s angle changes with the seasons.

Dust is a houseplant’s worst enemy; a heavy coating of dust will clog the plants’ breathing pores and will stress or even kill a houseplant. A great deal of dust blows into our homes in the central San Joaquin Valley. Wash dust off leaves frequently with a damp paper towel or by taking the plant to the sink and washing the leaves with a gentle spray or stream of tepid water.

Elinor Teague: etgrow@comcast.net