Wintering Your Plants
As the days get naturally shorter in fall and winter, plants may go dormant as they would in their natural habitat. The secret to helping plants survive winter is adjusting care routines to suit seasonal growing conditions. Review the basics to give your houseplants top-notch care this winter. Whether your indoor plants are always indoors or have been brought in from outdoors for the winter, there are important considerations.
Bringing Plants in from Outside
One of the most common issues houseplants have when coming back indoors is bringing unwanted pests with them. Check your houseplants thoroughly for small insects like aphids, mealybugs and spider mites and remove them. These pests can hitchhike on the plants you bring in for the winter and infest all of your houseplants. You may even want to use the hose to wash off your houseplants before bringing them in. This will help knock off any pests that you may have missed. Treating the plants with neem oil can help as well.
In winter, the sun slips lower in the sky and light levels near windows drop up to 50 percent. Houseplants that grow near a sunny eastern or northern window in summer may need a southern or western exposure in winter. Likewise, plants near western or southern windows that need filtered light in summer may be able to withstand direct sun in winter. To help plants cope with changing light levels:
Move plants closer to windows, if possible.
Clean windows to allow maximum light transmission.
Shift plants to new locations near brighter windows for winter.
Wash dust off plants so leaves can make maximum use of available light.
Add artificial light. Fluorescent bulbs provide adequate light. They’re cheaper than traditional grow lights and produce less heat. Position bulbs 4 to 12 inches away from plants for effective results.
Most houseplants are tropicals and prefer temperatures between 65° F and 75° F during the day and about 10 degrees cooler at night. For many plants, temperatures below 50° F can cause problems.
Avoid placing plants near cold drafts or heat sources.
Keep plants several inches away from exterior windows.
In cold regions, if windows frost overnight, move plants away from windows at dusk. You can also slip a heavy shade or other insulating material between plants and glass.
Homes may offer only 5-10 percent relative humidity in winter. Tropical plants which are often houseplants like 40-50 percent. Signs of low humidity stress on plants include brown leaf tips and appearance of pests like spider mites. A simple, easy way to add humidity is to place plants on top of a pan filled with pebbles and water. However this is not suggested for succulents.
The most common problem houseplants suffer from in winter is overwatering. About 95 percent of houseplants need soil to dry out almost completely before watering. How can you tell if plants need water?
Don’t just spot test the soil surface. Plants need water when the root zone is dry. Poke your finger into soil up to 2 inches. If the soil is dry, water.
Lift the pot. Soil is lighter when it’s dry. Learn how wet soil feels by lifting pots immediately after watering.
If you humidify winter rooms, plants won’t need water as often. Dry air means watering.
Exceptions to drying out between watering: Potted citrus and ferns require consistently moist soil. Always research plant moisture needs if you’re unsure.
When you do water, never allow plants to sit overnight in water that collects in the drainage saucer.
In coldest climates like Michigan where natural light levels are low, do not fertilize houseplants in winter. Resume fertilizing when outdoor plants wake up in spring.
Note changes in light in your home and adjust accordingly.
Avoid placing plants near heat vents and drafty locations.
Do not fertilize in winter
Be VERY careful not to over-water. Most plants go slightly dormant and only need to be watered when they are very dry. Check plant instructions to make sure your plants don’t need additional water in winter because some do.
Consider putting tropical plants on a tray of pebbles with water to add humidity.