Roses Can Be Winterized By Mulching, Tying Canes

Q: Even though we've had some freezing weather now, I haven't cared for my roses. Is it too late?

A: You can still winterize your roses, since there's been no prolonged freezing spell, but be sure to do it right now!

Tie any canes that will whip around in wind, especially the longer canes of climbing roses. Don't do any major pruning until late February, around President's Day. The cold weather will help to force the roses into dormancy. Being dormant is great winter protection. If the plant continues to grow, hard freezes can damage or kill the rose. And you may have noticed that during mild spells roses leaf out and may even poke out a few straggly flowers. It's time for the rose to be completely dormant.

Trim off all buds and remove and discard all foliage. Scoop up any fallen leaves that are under the plant. You may feel a bit strange and even heartless doing this. Put these leaves in trash or Clean Green pickup. Don't compost any of the foliage or leave it under the bush. You're doing this for two reasons - first, removal of the leaves forces dormancy. Second, you are getting rid of fungal residues that cause black spot, rust, and powdery mildew on next year's leaves. If the leaves are left under the bush, rain can splash residual spores back up on the emerging leaves next spring. So clean up!

After you've cleaned up around the roses, mulch over the bud unions. That's the swollen area of the stem about 4 inches (or less) off the ground. Use clean deciduous tree leaves, finished compost, or even sawdust. Remove this mulch when the rose begins to grow in spring.

Roses in containers, especially tree roses, require special protection. Again, remove all the foliage. Remember that roots in containers are exposed to deeper and more damaging cold than roots in the ground. Move the containers on to soil and pile leaves or compost around the pot up to and over the soil level. If you have a tree rose, wrap the trunk in gray foam-like pipe insulation or swaddle it in burlap. You can also swathe the top of the tree rose if you are in a particularly cold area, but the most important areas of protection for potted roses are roots and trunk.

Gardening runs Friday in Scene and Sunday in Home/Real Estate. It is prepared by Mary Robson, Master Gardener program director, Holly Kennell, Washington State University/King County Cooperative Extension agent, Susan Miller, integrated pest management specialist, and volunteer Master Gardeners.