I’m looking for detailed information on how well Pacific wax myrtle (Morella aka Myrica californica) performs in northwestern Washington. Also, when is the best time to prune this shrub for renovation?
Morella californica is native to the Pacific Northwest (including the southern part of the Washington coast), and is generally recommended for planting in our area. It’s very fast-growing during the first 10 years after planting, and is tolerant of drought, wind, and salt spray. It’s also tolerant of varying soil conditions, and takes well to pruning.
However, during the past decade, it’s been found to be susceptible to a leaf-blight disease, Phytophthora taxon morella. Many Phytophthora species are primarily root-rot diseases, but this one is a foliar disease. It’s important to remove affected growth and clean up fallen leaves. New leaves produced in late fall and winter are very susceptible, so pruning should be done in spring. Infections tend to fall off as the weather warms. In the past, California wax myrtle was considered both sun and shade-tolerant, but plants growing in shady conditions are more susceptible to this disease than plants growing in open conditions.
A friend asked me about screening two large propane tanks that, unfortunately, have had to be placed in front of their home on Camano Island. She mentioned wisteria to me and I shuddered. I’ve seen this plant do a lot of damage to trellis and home alike. Can you recommend, instead, an evergreen solution to this problem?
I am not familiar with the size and shape of propane tanks, but perhaps evergreen shrubs might work to screen them. A concern would be the proximity to the house, and any needed clearance for paths, doorways, and windows. I think you are right to avoid Wisteria. Does your friend prefer the idea of planting vines, or would shrubs be acceptable?
Here are a few suggestions for evergreen shrubs, with links from the local web site, Great Plant Picks:
Some good information is also available about plants for screening (from Virginia Cooperative Extension) and vines, especially evergreen vines such as Trachelospermum jasminoides, which might be a good solution. Local garden writer Valerie Easton on has written helpfully about hedges, as well.
I am looking for evergreen hedges that will tolerate a windy site. Do you have any suggestions?
Sunset Western Garden Book (2007 edition) has
a list of wind-resistant plants. From that list, there were a few plants
which meet some of your site’s needs (evergreen, fast-growing, about 7-10
feet tall). They are:
- Arbutus unedo (Strawberry tree)
- Arctostaphylos (Manzanita)
- Ceanothus
- Chamaecyparis
- Cotoneaster
- Escallonia
- Morella californica
- Pinus species (you would need a dwarf pine for your size limits)
- Pittosporum (many of these grow taller than 10 feet over time, but P.
tobira might work)
- Pyracantha
I don’t know if it is tolerant of winter winds, but Osmanthus delavayi
makes a nice, dense evergreen hedge with flowers, and reaches about 8
feet. It grows fairly quickly also.
Two good resources for finding more information on the plants above are
Oregon State University’s Landscape Plants and Great Plant Picks.
Also, I found an article (no longer available) on wind tolerance from Colorado State University Extension which may be of interest. Here is an excerpt about the physical characteristics of wind tolerant plants:
“When considering which trees and shrubs do well in windy conditions,
examine the shape and thickness of the leaves, stems and branches.
Wind-resistant trees usually have flexible, wide spreading, strong
branches and low centers of gravity. Wind tolerant shrubs often have
small, thick or waxy leaves or very narrow leaves (or needles), to help
control moisture loss. Plant species that have large, flat leaves “catch”
wind. These plants have a tendency for branch breakage when strong gusts
blow, or if laden with heavy, wet snow.
Evergreen (conifer) trees are an excellent choice, having needles and
being flexible in high winds.”