As daylight diminishes and evenings grow darker, temperatures inevitably dip. Seasoned gardeners will appreciate that freezing temperatures are a part of the natural progression as we transition from fall into winter. Frost helps reduce insect and fungal pests by decreasing their populations, is an important cue for bulbs and tuberous roots, and knocks herbaceous perennial foliage back down to the ground so that a new cycle can begin in the Spring.
While cold temperatures are to be expected, even welcomed, there are a few key strategies that gardeners can employ to make sure cold temperatures don’t do any unnecessary damage to plants in the ground, pots, or indoors.
Protect Potted Plants
Potted plants out in the landscape should be attended to before temperatures drop, especially if they contain broadleaf evergreen shrubs, plants with buds or flowers, or herbs that you hope to keep harvesting throughout the winter.
- Move all potted plants near the house to a covered location such as a porch. Place plants on a plant caddy to make rearrangement easier. Consider adding boards or old windows to open porch sides to reduce damage from cold winds.
- Group potted plants together to reduce surface area around exposed pots. Burlap or old towels around bases of pots can help insulate them to prevent damage to roots and ceramic pottery.
- Water all pots thoroughly. Wet soil is a great insulator for roots, and even if the potting soil freezes, the roots will be better protected than if they experienced cold temperatures while dry.
- Cover tops of plants with a frost cloth or horticultural fleece. Using cloth overnight helps keep evergreen plants from getting frost burn on the tips of their leaves.
- Bring tender plants indoors if temperatures drop below 28°F. Citrus and plants hardy to higher than Zone 9b should be brought into a cool, frost-free environment like a garage or mud room until the coldest weather passes.
Prune Plants in the Landscape
Ice storms have become a new reality in the Pacific Northwest, and the weight added by ice forming on wet branches does more damage than cold temperatures alone.
- Mulch the soil around plants with compost or straw to protect the crown, but don’t overcrowd the base of plants.
- Stake newly planted trees and shrubs to prevent damage from winter wind or ice.
- Prune roses (we like Felco pruners) back to waist height to prevent thin, tender branches from breaking and creating wounds that leave the rose bush vulnerable to diseases.
- Remove branches (with a pruning saw) from evergreen and deciduous trees that might hit the side of the house, impede walkways, or damage plants below them if they become weighed down.
- Winterize irrigation systems and drain water features to prevent damage during freezing events.
Don’t be tempted to prune too aggressively before a storm—take stock after cold temperatures have passed and follow our winter weather recovery tips to help your landscape look its best.
Relocate Indoor Plants
Even indoor plants can struggle when temperatures dip down, drafts increase, and heating systems work overtime to keep up.
- Move plants away from single-pane windows or areas where drafts enter the house.
- Avoid placing plants near heating sources, as hot air can dry out roots and leaves and add unnecessary stress.
- Mist your houseplants to keep humidity levels high.
If the power goes out during a winter storm, follow our guide to help provide emergency care to indoor plants during extreme weather events.
We Are Here to Help
Our knowledgeable garden center staff and full-service landscape crews are here to help. Stop by to pick up supplies that will help minimize damage to your plants. Stay safe and warm, and remember—we can weather the storms together.