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Winter Care of Houseplants
Environmental conditions indoors during the winter months are difficult for many houseplants. Good care during the winter months can help houseplants deal with the stressful conditions during this time period.
Most houseplants prefer daytime temperatures of 65 to 75 degrees Fahrenheit and night temperatures of 60 to 65 degrees Fahrenheit. Temperatures below 50 degrees Fahrenheit or rapid temperature fluctuations may harm some plants. Keep houseplants away from cold drafts, radiators, and hot air vents. Also make sure houseplant foliage doesn't touch cold windows.
Many houseplants prefer a relative humidity of 40 to 50 percent. Unfortunately, the humidity level in many homes during the winter months may be only 10 to 20 percent. Humidifiers are an excellent way to increase the relative humidity in the home. Simple cultural practices can also increase the relative humidity around houseplants. Grouping plants together is an easy way to raise the humidity level. The water evaporating from the potting soil, plus water lost through the plant foliage, will increase the relative humidity in the vicinity of the houseplants. Another method is to place houseplants on trays (saucers) filled with pea gravel or pebbles. Add water to the trays, but keep the bottoms of the pots above the water level. The evaporation of water from the trays increases the relative humidity around the plants.
In general, houseplants require less frequent watering during the winter months than in spring and summer. Watering frequency depends upon the plant species, composition of the potting mix, environmental conditions (temperature, light, and humidity) and other factors. When watering houseplants, continue to apply water until water begins to flow out the bottoms of the pots. Discard the excess water.
Fertilization is generally not necessary during the winter months as most houseplants are not growing during this time. Indoor gardeners should fertilize their houseplants on a regular basis in spring and summer when plants are actively growing.
Dust and grease often accumulate on the leaves of houseplants. The dust and grease not only makes them unattractive, it may also affect plant health. Cleaning houseplants improves their appearance, stimulates growth, and may help control insects and mites.
Large-leafed plants may be cleaned with a soft sponge or cloth. Wash the foliage using a very mild solution of dishwashing soap and tepid water. Another method is to place plants in the shower and give them a good "bath." Be sure to adjust the water temperature before placing the plants under the shower head.