Worth growing in the garden merely for its fragrant white or pale pink blossoms in spring, the Nanking or Machu cherry (Prunus tomentosa) bears edible red fruits, too, ripening in midsummer. More of a large, spreading shrub than a tree, it matures 6 to 10 feet tall and 10 to 15 feet wide. Plant it where it receives no less than eight hours of direct sunlight daily and in any non-soggy soil, regardless of fertility or pH. Nice in a shrub border or as a mass planting, grow it in U.S. Department of Agriculture hardiness zones 2 through 6.
Cut away all dead, damaged or diseased branches across the plant using hand held pruners. Make the pruning cuts 1/4 inch above a lower alive branch, leaf, or dormant bud. If the branch to be pruned is larger than 1/2 to 3/4 inch in diameter, use loppers. Do this pruning any time of year.
Wait until early summer to conduct any further pruning on the Nanking cherry tree according to Dr. Laura G. Jull of the University of Wisconsin, Madison. This reduces sap bleeding from wounds and lowers the risk of pest invasion. Ideally prune on days with low humidity and no chance of rain.
Reduce the length of branches by no more than one-third in early to midsummer. Choose for pruning branches that are overly long, irregular or leggy; pruning every branch is not necessary. Make the pruning cut with a hand pruners 1/4 inch above a lower branch junction, leaf or dormant bud. This pruning technique is called "heading back." Remember that overpruning removes potential fruit crops.
Remove any suckers from the base of the plant. Suckers are vertical sprouts that come up from the trunk base or surrounding roots, creating a thicket. Cut these suckers off flush with the ground.
Cut off lowermost branches to expose a bare trunk or multiple trunks and maintain the Nanking cherry shrub to look more like a tree. Cut off laterally growing branches 1/4 inch flush with the trunk with the hand pruners or loppers if their diameter is greater than 1/2 to 3/4 inch. Clear the bottom 2 to 4 feet of trunks of these lateral branches to create a more tree-like shape. Do not overprune, as too many branches cut away at any one time leads to production of more suckers.
Things You Will Need
- Hand pruners (secateurs)
- Early summer is the best time to prune, followed next by late winter when the plant is still dormant.
- Branch pruning done each year, reducing them by one-third their length, on no more than one-half of all the branches on the Nanking cherry helps maintain a vigorous, well-shaped plant.
- Nanking cherry naturally grows into a spreading, branched plant, so to form an upright tree, considerable and repeated pruning is needed.
- Do not prune this plant past midsummer and certainly not during the fall months when frosts are soon to follow.