Darrell Blackwelder: Answers about trees and shrubs

Published 12:00 am Friday, July 5, 2019

Plant growth has accelerated for most plants with the warm weather and recent afternoon showers. It’s surprising how well landscape plants are doing, especially summer blooming trees and shrubs. Below are a few questions posed to me during the past few weeks about trees and shrubs.

Question: I was driving by an office building in Salisbury yesterday and noticed small crape myrtles planted in the landscape. They are very beautiful and in full bloom, yet they are planted very close to the building. Do these trees have to be pruned annually to keep them small?

Answer: No, the crape myrtles planted are most likely newer cultivars that have a very low growing habit which can also withstand full sun in very hot locations. The benefit of these crape myrtles is that these plants are very small and never have to be pruned to control their height. There are dwarf type crape myrtle cultivars available that require very little or no pruning. Go to https://extensiongardener.ces.ncsu.edu/extgardener-popular-crape-myrtles-now-in-smaller-sizes/ for a list of crape myrtle cultivars for your consideration.

Question: My family was at the coast this past week and noticed a small tree that looked just like a mimosa tree, but it had leaves that were dark brown, almost black. The tree had blooms just like the native trees we see along the roadway. Is this a new type of mimosa tree?

Answer: Yes, even though native mimosas are growing everywhere and considered an invasive species, there are newer cultivated varieties of mimosas that have different characteristics of leaf and bloom color. The cultivar you observed is Mimosa Summer Chocolate. There are also cultivars featuring white blossoms.  Native mimosas are considered invasive plants and are subject to soil borne diseases and are short-lived. However, newer mimosa cultivars have more disease resistance.  These newer cultivars are difficult to locate, but the seed may be purchased online from seed companies.

Question: Someone told me that there was an evergreen dogwood tree that has blooms very similar to that of a kousa dogwood. Can you tell me about this new type of dogwood?

Answer: The tree you referring to is probably a Cornus Angustana Elsbry, Empress of China dogwood. The small tree has profuse blooms, producing up to 150 creamy white blooms per branch in late spring into early summer.  It is a small evergreen tree with dark, shiny leaves that can obtain a height of 12-15 feet. This tree prefers morning sun and afternoon shade. They can be difficult to find, but some retail outlets may occasionally stock the tree.

Darrell Blackwelder deblackw@ncsu.edu is the retired horticulture agent with the North Carolina Cooperative Extension Service in Rowan County.