The Grounds Guys' Guide to Winter Plant Care
If you live in a cold climate, winter can be taxing on your garden. Fortunately, we have you –and your plants – covered with our guide to winter plant care. Follow our advice and your plants will live to see the spring.
Indoor, Winter Plant Care
You can and should bring potted outdoor perennials back inside for the winter, especially if they aren’t hardy enough to survive winter conditions. However, you should never bring a diseased or infested plant inside. Assuming you have enough natural light, the best varieties to over-winter inside as houseplants include:
- Bay trees
- Sentimental or expensive plants
- Small pepper and tomato plants (which will continue to produce fruit all winter long)
If you don’t have enough sunlight for tender perennials, many survive a period of winter dormancy. A cool garage or cellar with temperatures between 20 and 40 degrees keeps the plants dormant without harming them. Whether you keep your houseplants plants in full bloom or let them go dormant, don’t forget to water them all winter.
Outdoor, Winter Plant Care
Most of the perennials in your garden should stay outside all winter long. With the proper care, you can help ensure your plants survive until spring.
Typically, container plants can survive outside if their hardiness rating is two zones lower than the zone you live in. If you lack the space or the natural light to bring your container garden inside, your plants have the best chance of survival if you follow these tips:
Temporarily transplant potted perennials into the ground or bury the plants, pot and all, so the soil can better insulate the roots. To help prevent rotting or frozen roots, slightly tip any potted plants you bury to help promote drainage.
If transplanting isn’t an option, group all your potted plants together by the side of your house so they’re relatively protected from snow and harsh winds.
Be aware that untreated terracotta and other porous containers are likely to absorb water and crack when the temperature drops below freezing.
Prune Your Plants
Winter is the ideal time for pruning. Follow these basic tips:
- Remove dead or diseased branches first.
- Remove crossing or rubbing branches next.
- Starting at the center and moving outward, thin the canopy to increase air circulation.
- Keep the tree balanced and symmetrical as you prune.
- Cut back to a bud or branch to reduce dense horizontal growth.
- Never cut flush to the trunk. Leave a natural collar so the wood can heal properly.
Mulch the Garden
Mulching in the winter serves a unique purpose. It insulates the ground – not for warmth but to keep it frozen. Hardy plants can survive in frozen soil, but not in repeatedly freezing and thawing soil. Cover your garden with two to four inches of mulch, bark, or leaves, including any potted plants you bury, to reduce damaged caused by the freeze-thaw cycle.
Cover Your Plants
The primary goal of plant covers for cold weather is to protect plants from frost. Cover your garden at night any time the forecast predicts below-freezing temperatures. Implement these techniques when using winter plant covers:
Use a blanket, frost barrier fabric, or burlap – not a plastic tarp.
Stake or tie down winter shrub covers over the root zone to more effectively protect plants from freeze.
Don’t bind winter plant covers around stems or trunks to avoid damaging the plant.
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