I’ve pretty much put all my plants to bed for the winter. I’ve taken some inside, but most of them can stay outside for the winter without being harmed by the cold temperatures. There are a few, however, that need some extra care.
Plants That May be More Sensitive to Cold
The sensitivity of your plants depends on geographic location and your USDA cold hardiness zone. If you’re like me, and try to push the season, you probably have a few plants that are not as cold hardy as the majority of your plants. Figs are one that I have a few of. Some cultivars, like Chicago Hardy and Brown Turkey, do okay in zones 4-6, but some of the less hardy ones, like Celeste, may die in cold temperatures. Sometimes they will die back on the top, only to grow back from the roots in the spring. Other years they may die out entirely.
Other plants that may need some extra care are some more southern species of conifers, crepe myrtles, butterfly bushes, some roses, and rosemary. I’ve had some success overwintering tropical ginger and lemongrass outside when I lived at an elevation of 1,500 feet above sea level, but here in the mountains (zone 6b/76a) at 2,500 ft, they almost never survive.
Techniques for Helping Sensitive Plants Survive Winter
- Some plants do well if you dig a trench and bury the entire plant in the ground. Tree roses do especially well this way. Be sure to dig down a few feet to get below the initial frost line at the top of the ground. Bury the plants well and mound the dirt on top of them for extra protection.
- You can use a buffer like leaves or straw to help insulate plants against the cold. When I was living in Minnesota (zone 4) we had problems getting our butterfly bushes to survive. So we made a ring around the plant with fencing, then filled it in with leaves or straw. They did much better after we started doing this.
- Another good buffer is snow. Any plant you want to survive the winter can be mounded with snow, which acts as an insulator like leaves and straw. If you get a few nice days in January or February, don’t be tempted to remove the snow to let the sun get to them. This is almost always a mistake as the plant may start to put out leaves and start its spring growth, only to have those leaves and branches freeze when the cold weather hits again.
- Along the same lines, don’t do any pruning on your trees and shrubs in the fall. This will encourage growth which will probably freeze and cause damage to the plant. Wait until at least March to do any pruning. Some plants, like apples and peaches, need to be pruned in the dormant season, and March is usually best for this.
- If you have plants in containers, like dwarf Alberta Spruce in pots on either side of a door, you can protect the plant by wrapping the pot in burlap. This will help insulate the roots and give the plants a better chance at survival. Add a bow and you’re set for the holidays!
- Speaking of the holidays, put those Christmas lights to work in the cold weather. If you are in a normally temperate location and you are going to have freezing temperatures that would not normally be a problem, wrap your plants with lights and place a tarp over them. There should be just enough heat from the lights to protect the plants, but not enough to burn them or risk a fire. I use this method in the spring if my apple trees bloom early and there’s a danger of frost after.
- Make use of micro climates. I’ve lost my figs many times in the cold. My new house has a stone exterior on the south side, and it stays warm into the night even when it’s cold. I planted my figs in a corner on the south side and expect them to do much better.
- I also have a few more sensitive herbs like some of my mints, rosemary, and lemongrass. For them I made a straw home. I took four bales of straw and made a cube with the center open. Then I put all those herbs inside and covered them with leaves. I then covered the leaves with a blanket, then a tarp that I weighed down with concrete blocks. The straw will insulate the plants and the tarp will keep much of the rain and snow out so they don’t freeze.
One more tip…
If all else fails, and you know there is freezing weather coming, you can spray down your plants with water and let them build up a coating of ice on the outside. It sounds counterproductive, but the ice will actually help the plant survive instead of harming it.
Have you used an unusual method to keep your more sensitive plants safe in the winter? Let us know! Share in the comments below.