11 Ways to Keep Houseplants Happy in Winter

Whether your potted plants live indoors year round or have sought temporary shelter from freezing temperatures, they're probably looking a little sad these days. Are you doing something wrong? Or have they just gone dormant until winter ends? We asked horticulturalist David Clark (who is coddling his own houseplants through a severe winter in upstate New York) for advice about how to perk up winter-frazzled houseplants. Here are his top 10 tips (plus one of our own):

Above: Photograph by Mieke Verbijlen.

 Clark, an instructor at the Buffalo and Erie County Botanical Gardens, likes a challenge when it comes to houseplants: he has managed to keep a 4-foot gardenia topiary alive for four years and has collected more than 300 different orchids. But whether you're nursing something finicky like an African violet or a hardy Mother in Law's tongue, your houseplants are going to have a harder time in winter. Here's how to make them happier:

1. Cut back on water.
2. Give them sunshine.
3.  Add moisture to indoor air.
4.  Stop fertilizing until spring.
5.  Dust your plants.
6.  And give them a bath once in a while.
7. Crank up the heat, then turn it way down (every day).
8.  Avoid re-potting if possible.
9. Conduct a weekly bug inspection.
10.  Give sick plants a natural tonic.
11.  Sing them lullabies (could it hurt? plants love music).

Above: Photograph by Michelle Slatalla.

Water: "Most plants only need water once a week in winter," says Clark. "They will kind of go dormant, especially if they're plants that grow outdoors in summer and they've come from that bright light into a home with lower lighting and lower temperatures."

Above: Photograph by John Merkl.

Sunshine: Put them in the sunniest spot in the house; most them to follow the sun if necessary. "Most plants will not thrive in a north-facing window because they need more sun," says Clark. The best? A window facing east; you will get sun from 7 am to 11 am and "it's not harsh, like what you'll get in a western facing window," he says.

Above: Photograph via Design Sponge.

Humidity: Most plants thrive with levels of from 50 to 60 percent humidity; in a house the humidity level can go below 35 percent. "In a situation like that, make them a little miniature greenhouse by tenting them under a big plastic bag," says Clark. "Or take a shallow tray, fill it with 2 inches of water and gravel, and set your potted plant in it." As the water evaporates, it will create humidity around the plant.

Tonic for Sick Plants: The most common disease that plagues houseplants is leaf spot—yellow or brown spots that develop on an outer leaf and move inward. If your plants are suffering, mix a tonic and spray it on their leaves: Dissolve 4 teaspoons baking soda in a gallon of water and add a few drops of Murphy's oil to make a suspension.

Above: Photograph by Electronomo via Flickr. 

Keep plants clean: "When they get dusty, that causes plants not to breathe. It plugs their leaves, which have little pores called stomata," says Clark. "If you cover a leaf surface with dirt, it won't get the full effect of sunlight and photosynthesis will be slowed."

Solution? For smaller plants, give them a bath in a sink with a sprayer. Larger plants can go into the shower. Wipe leaves with a damp sponge. Then off their leaves so they don't drip all over the floor.

Are you bringing a potted lemon tree indoors? See How to Keep a Potted Citrus Tree Happy in Winter. Bug problems? See Goodbye, Gnats: Pest-Free Potting Soil.