Rose Report winterizing roses
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Kentucky coffee tree
Sweetgum ‘Rotundiloba’ When I was younger, I cut a big black walnut tree down thinking it was dead though it was very much alive. You see, black walnuts (Juglans nigra) lose their leaves early. In dry years, leaves start coming down in late August and trees are leafless by September. It must have been a dry year. To be honest, I didn’t feel entirely bad since my friend convinced me it was dead, it was on his property, and he split and burned the wood in his wood stove that winter. That said, I learned my lesson. Red buckeye (Aesculus pavia) and Ohio buckeye (Aesculus glabra) lose their leaves in late summer or early fall and so can serviceberry (Amelanchier arborea) and rusty blackhaw viburnum (Viburnum rufidulum). Young witchazels (Hamamelus veralis and H. virginica) at times have a quality that some may find unattractive. The dried winter leaves stick to the stems through its bloom period (November through February), hiding the winter flowers. This normally happens on young trees (less than 5 to 7 years old) but sometimes lasts for over a decade. Due to genetic diversity, some seedlings are more prone to this condition than others. This also occurs on oak seedlings during a period of juvenile vigor, when plants are growing rapidly. Most oaks out-
grow this before they turn ten, but not all. However, the persistent dried leaves on witchazel and young oaks do provide a privacy screen, which is an attractive quality. Speaking of leaf challenges, arrowwood viburnum (Viburnum dentatum) leaves smell like old gym socks when it rains. Unless you like this odor, plant them as far away from your nose as possible. They have nice burgundy and/or pinkish fall color, dense stems that birds prefer to nest in, and clusters of purple berries that birds devour. When you pry money out of your pocket to purchase this plant, remind yourself how important plant diversity is for attracting wildlife and consider the benefits of keeping fallen leaves in garden beds. Many butterfly, moth, and bee species overwinter in or beneath fallen leaf litter and will die if you rake and remove the leaves. Consider raking fifty percent fewer leaves this year in your garden beds and planting smaller-leaved native tree species that blend in where leaves float down into planting beds. There are so many different ways to garden beautifully while promoting wildlife. It will take all of them to turn around the current wildlife decline occurring in our neighborhoods. Garden with purpose; make a difference today!
or many years I have been teaching a class on winterizing roses, and I am always happy to see the enthusiasm that gardeners have for learning how to care for their roses in winter. Many new gardeners diligently take notes ensuring their roses success and many of the seasoned gardeners listen and watch for new or updated information. The most asked question is, “when do I prune my roses back and when do I mulch them for the winter?” I actually start winterizing in mid-October by defoliating two to three feet high on the rose bush, this slows down the rose. Don’t worry if you didn’t defoliate the rose in mid-October. You can do this step when you prune your roses later in November, as it will still be helpful for your rose and will make cleanup in the spring much easier. I recommend pruning your roses in mid-November cutting the roses down to 24”-30”. This keeps your roses from whipping in the wind, which causes physical damage to the roots and canes. I also rake and pick up all the leaves and rose clippings from the bed. Next I spray a contact fungicide on the soil and the rose canes to keep overwintering black spot spores under control. If you do not use fungicides in your garden you can still get good results by removing all leaves and cuttings from your beds. Mulching roses should be started mid-November or around Thanksgiving. Delaying mulching until this time will ensure you keep the cold in the soil. You may wonder why I want the soil cold. The answer is to protect the rose from the alternate freezing and thawing during a normal winter and from desiccation (loss of moisture from canes and roots).
For the last two years I have been using compost to mulch my roses and I mound this up around 6-8 inches at the base of the rose. Other mulches such as wood mulch or leaves are suitable for mulching roses as well. If you decide to mulch with leaves I would recommend using some type of fence (chicken wire or cardboard boxes) around your roses to keep the leaves from blowing away. During the winter, make sure to keep an eye on how much precipitation the garden receives. Water your roses if we have a dry winter, since dry conditions can be very detrimental to a rose’s winter survival. Climbing roses in our area should be tied to a structure so they do not whip in the wind but do not cut them back, as some varieties will bloom on second year wood. You can put straw and burlap around the canes on your climbing roses for extra protection, but I have found most years this is not necessary. Miniature roses do not need as much protection as larger roses, so if you rake several inches of leaves into the rose or use a small mound of compost for protection, that will suffice. Old roses usually don’t need winter protection at all and you don’t have to prune them. Tree roses will need to be brought in the garage and watered throughout the winter until next spring. If you would like to take my class on winterizing roses this year, you can go anytime to YouTube and look up Judy Penner. I have a video on winterizing roses and if you would like to be notified on future videos just like and subscribe to my channel. Remember to Stop and Smell the Roses!
JUDY PENNER Expert Rosarian
Judy Penner is Expert Rosarian at Loose Park, Kansas City, Missouri. You may reach her at judyssecret gardens@gmail.com.
The Kansas City Gardener | November 2020
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