One born every minute

Suckering trees and shrubs

By Amy McDowell

In horticulture, there’s one born every minute. And there I was in the front yard in the chilly knee-deep February snow, pruning the suckers from around the base of my spring snow crabapple. I had read that if you prune suckers during the winter months they don’t grow back as quickly.

As the weather warmed in spring, tiny red buds emerged at the base of the trunk, and soon enough skinny suckers were growing up at the base of the tree again. Exasperated, I realized I’d been had—the only thing that had delayed the new shoots was winter.

Suckers are not all bad. Most of my favorite shrubs have a suckering habit that results in a broad mound of growth and a beautiful shape when mature. There are a great number of suckering shrubs, including lilacs (Syringa species), Hydrangeas, Spireas, pussy willow (Salix discolor), serviceberry (Amelanchier arborea) and bottlebrush buckeye (Aesculus parviflora). Many of these form dense thickets that create wonderful privacy when used as hedges. Frequently, you can dig the suckers from around the base of the original plant and use them to extend plantings around the garden.

Staghorn sumacs (Rhus typhena) ablaze in red and orange right now, and elderberry (Sambucus canadensis) sucker to form large, open colonies. Both are fairly aggressive for a small garden, but regular lawn mowing at the edge of the colony is all that’s needed to fight back their spread.

Suckers are a sign of a plant’s genetic vigor. A non-suckering shrub like purple-leaf sand cherry (Prunus cistena) can fall prey to collar rot in heavy clay soil, but if it had the ability to sucker, young new stems would keep the shrub alive as the older stems succumbed. If sand cherries suckered, it would vastly improve their durability and longevity in central Iowa landscapes.

Despite all of the great suckering plants out there, it’s still tough to come up with an advantage to the raggedy suckers at the bases of crabapple trees. Tender rabbit fodder, I guess, to slow their attacks on the tasty trunk bark.