Controlling Conifer Height
Q: Can we keep our conifers down to 10 feet?
We planted a group of evergreen trees in our yard some time ago: a blue spruce, a Norwegian pine, and one that I can't identify. The biggest one is about 10 feet tall, and we'd like to keep them all about the size they are now. Is there a way to keep them from getting taller?
—Kathy Spencer, Oostburg, WIS.
Roger Cook replies: Yes, it's possible to keep your trees about the same size they are now, but it will be a constant battle. They normally grow 30 to 60 feet tall, depending on the species, and can reach 10 to 30 feet in width. To keep them at about their current size you'll have to chop off their tops and aggressively prune the lateral branches. The best time to do this is in the winter, while the trees are dormant. (See tips on how to prune conifers.)
Topping a tree isn't a step to be taken lightly, because you're interfering with the natural way a tree grows. So here's another possibility to consider: Move one or two of them and let them grow unimpeded. A local landscaping company can tell you what it will cost to relocate them.