Alive or dead? Repercussions from last winter’s capricious cold are showing up on many plants this spring.
If your garden looks like ours, damage ranges from a few plants flat out dead to ones mostly living with a mix of healthy and blackened branches. I’m surprised how many shrubs and trees fared just fine, even though zero degrees and below hit before most plants had time to reach full dormancy last fall.
Plants can better withstand severe cold after they’ve reached dormancy, and that comes from a gradual period of cooling temperatures. So minus degrees in January is a lot more amenable to plants than last November’s pre-Thanksgiving blast.
It’s time to carefully scrutinize your plants. Most shrubs and trees are showing plenty of swelling buds or have already leafed out. Any deadwood should be obvious.
With pruners, loppers and perhaps a sharp knife in hand, savor our lovely spring weather by heading out to check your landscape, plant by plant.
Dead stems should be eliminated. Blackened stems are a pretty good giveaway. If it’s not obvious whether it’s alive, take a sharp knife and cut into the side of a stem. If the cut portion shows light coloring and looks healthy, the stem is fine. If it looks dried out with a discolored, muddy brown or black appearance, then prune back until you find a healthy green stem just above a side shoot or bud.
Make this an opportunity for improving the looks of some of your shrubs or trees if they’re out of proportion to the area or too dense.
First, remove anything dead. Next take out crossing or damaged branches, then thin out the center of the shrub so sunlight can reach into it. Now stand back and take a good look at your plant. Trim branches as needed to even up the shrub.
Removing no more than one-third of a shrub in a year is the general rule of thumb, but winter-killed wood is a different story.
We have (oops, had) three roses growing on the south side of our home, where they thrived on reflected heat from the house. Being in such a warm spot, they were less prepared for November’s vengeance than plants on the north side. Only Rosa “Julia Child” survived. She’s a robust yellow floribunda with prolific blooms. I trimmed back the blackened stems to new side shoots that look healthy. Even though I couldn’t pick and choose for shape and spacing, she’ll fill out nicely.
A couple of nandinas (heavenly bamboo) are still looking iffy, although after cutting a stem and seeing green wood, I am confident they’re alive and will push up new growth. They’re best pruned at the base rather than part way up a stem, forcing up new shoots.
Sometimes a cold-damaged plant will have just enough stored energy to put forth a few new buds and then just shrivel up and die. We had a redbud tree go this route. Nothing can be done to save it.
Except for hydrangeas and other late-comers, shrubs and trees should be showing their stuff by now — if they have any left.
Selecting hardy plants that can withstand our occasional sub-zero weather is a smart investment. At times, we gamble buying a plant that’s marginally hardy because we really want that plant, but it can be lost in one bad winter.
Perhaps this spring seems that much sweeter after being zapped by a couple of really chilling cold snaps.
A WSU Master Gardeners of Chelan County column appears regularly in the Home, Garden section. Mary Fran McClure is one of four columnists featured.