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Sunday - February 01, 2009

From: Arlington, VA
Region: Mid-Atlantic
Topic: Shrubs
Title: Small shrubs for roof garden in Washington DC
Answered by: Barbara Medford


I am looking for a hardy evergreen shrub for a roof garden in DC. Needs to be 3-4 feet tall, evergreen, dense, survive the extreme wind, cold and heat.


This is a tough call. The first thing that would come to mind are the conifers, which by nature are dense, wind-resistant, etc. However, they not only all grow very tall, but are difficult to transplant, and certainly would not survive long in a pot because of long taproots. The limit in height is a challenge with almost all shrubs we looked at, but many popular species are now available in dwarf or shorter versions. These are usually selections developed by nurseries from naturally shorter versions of the shrub. One of our favorite shrubs, probably because we love the name, is Arctostaphylos uva-ursi (kinnikinnick). This is low-growing, dense and evergreen, often used as a ground cover. The others are all members of the Ilex or holly genus, and all would either require extensive pruning or the use of a dwarf version to stay within your size specifications. These plants are Ilex glabra (inkberry), Ilex opaca (American holly) and Ilex vomitoria (yaupon)

You can follow the links to pages on the individual shrubs, noting their prospective heights, blooms, etc. If you have difficulty locating the plants, go to our Native Plant Suppliers section, type in the name of your town and state in the "Enter Search Location" box and you will get a list of native plant nurseries, seed companies and landscape and environmental consultants in your general area. They will have contact information so you can inquire about the availability, especially of dwarf versions.

Arctostaphylos uva-ursi

Ilex glabra

Ilex opaca

Ilex vomitoria




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