Less light, slower growth
Shorter days and a lower sun mean much less light indoors. Plants respond by growing slowly or pausing altogether. Help them by moving them closer to windows, cleaning the glass, and wiping dust off leaves. A grow light can make a big difference for plants in darker rooms.
Water less often
Slower growth means plants use less water, and soil dries more slowly in cool rooms. This is the season when overwatering is most common. Keep checking the soil before each watering; many plants will need water far less often than in summer.
Watch the humidity
Indoor heating dries the air. Crispy leaf tips and edges are common in winter, especially on ferns, calatheas and other tropical plants. Group plants together, use a pebble tray, or run a humidifier nearby.
Mind the temperature
A spot right above a radiator or next to a heating vent will dry a plant out fast, and a draft from a front door can be just as hard on it. Windows need a little attention too: on very cold nights, pull plants back from the glass or close the curtain behind them, because leaves pressed against cold glass can be damaged.
Pause the fertilizer
Most houseplants don't need feeding while they're barely growing. Unused fertilizer can build up in the soil. Resume in spring when you see new growth.
Hold off on repotting
Unless a plant is in real trouble, such as root rot, wait until spring to repot.
Keep an eye out for pests
Spider mites thrive in warm, dry indoor air. Check the undersides of leaves when you water, and rinse plants occasionally in the shower to keep them clean.
When spring comes
You'll know the season has turned when new leaves start to appear. That's the moment to go back to regular watering, start feeding again, and repot anything that has outgrown its pot.
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