Homegrown: Prepare for rose pruning in April
We moved to a house that has several different roses, but we’re not sure of the type. We were wondering if we should cut the stems down or just leave them alone with their leaves still on the stems?
You’ll want to cut the stems down, but not quite yet. Roses are sort of stupid plants and if you prune them, they’ll respond by shooting out soft succulent growth too early in the spring that can often be damaged or killed by late frosts.
The time to prune roses can vary a little from year to year depending on the weather, but I usually like to do it sometime during the first week of April.
When it comes time to prune, the first order of business is to remove any dead or damaged canes. Once you’ve done that, you need to form the plant into the shape of an upside down cone with the center empty.
Select anywhere from five to 11 canes as the framework of the plant. These canes should be well-spaced around the plant, growing out from the center in all directions. You don’t want any of the canes crossing or touching another cane. If this is the case, one of the canes needs to go.
I also like to think about rotating out larger, woodier canes in favor of younger, more vigorous ones. This will keep the plant more vigorous with denser foliage and more prolific flowers.
Once you’ve selected the canes to keep, cut out all the others. Don’t leave any stubs, cut them off pretty flush. Then cut back the remaining canes to 12–24 inches from the ground.
Personally, I like to cut them back to about 12 inches, it keeps the plant a little more compact, but some people get a little queasy cutting their plant back that far.
The last thing to do is to paint all the cut ends with pruning paint to prevent cane borers from getting into your plant.
I hope this all makes sense to you. It’s difficult to explain. We have a description and some sketches on our website. Go to bookcliffgardens.com/PDFs/Planting-Roses.pdf.
I have a 3- or 4-year-old spirea bush of unknown variety and it flowers spring into summer and is pinkish in color. Can you advise when and how to prune?
What you probably have is a variety of Bumalda spirea. This type of spirea blooms late spring into early summer with deep pink to magenta flowers. Most of them don’t get very big, only up to 3 or 4 feet at the most with many shorter than that.
There are a number of varieties available, among them “Anthony Waterer,” “Goldflame,” “Neon Flash,” “Magic Carpet” and “Superstar.”
This type of spirea is best pruned early in the spring. So now is the time to get at it.
You can cut them down pretty hard (4–12 inches) and they will sprout back quickly and, since they bloom on new growth, they should bloom better for you as well.
There are varieties of Japanese Spirea such as “Little Princess” that shouldn’t be pruned now. You’ll want to do it right after it is done blooming later this spring.
They have lighter, truer pink flowers with no hints of the purplish that the Bumaldas have.
Since it’s harder to tell right now, you might want to bring us a sample of your plant to see if we can tell what it is.