How to Grow Japanese Gray Bark Elm
Graceful and easy to grow, Japanese zelkovas (Zelkova serrata), sometimes marketed as Japanese gray bark elms, are a popular substitute for American elm trees since they have the same vase-shaped growth habit. These useful trees have good fall foliage color and exfoliating bark that adds interest to the winter landscape. Japanese zelkovas grow well in United States Department of Agriculture Plant Hardiness Zones 5 through 8. Does this Spark an idea?
Instructions
-
-
1
Site your Japanese gray bark elm in full sun to partial shade. Autumn color, which varies from yellow to red and purple, is best in full sun.
-
2
Transplant young Japanese zelkovas in either spring or fall, as they're easy to establish in either season. However, young trees are susceptible to frost damage in the most northern part of their range, so in zone 5, transplant them in the spring so that they have a whole growing season to settle in before cold weather arrives.
-
-
3
Keep the soil moist for the first year or two while the tree establishes itself. After that, Japanese zelkova is drought-tolerant and needs supplemental watering only during extended dry periods.
-
4
Feed Japanese gray bark elms with a fertilizer formulated for shade trees. This encourages quick establishment and strong, healthy growth, which in turn helps protect the trees from insects infestations and diseases.
-
5
Spread a 2- to 3-inch layer of organic mulch around your tree to conserve moisture and discourage weeds that compete with the tree for water and nutrients. Always keep the mulch 2 to 3 inches away from the tree trunk. Using a mulch also lessens the chance that you'll nick the bark with the lawn mower or trimmer. Refresh the bark each spring.
-
6
Inspect your trees periodically for insects and diseases. Japanese gray bark elms are very resistant to Dutch elm disease, the devastating fungal disease that has destroyed so many American elms, but are not immune. Look for curling, wilting and yellowing of leaves high in the canopy. Dutch elm disease is spread bark beetles; if you find beetles on your tree, consult with your local garden center or extension service for advice. In some parts of the country, zelkovas are also susceptible to Japanese beetles, which feed on the foliage only and don't carry Dutch elm disease. Japanese beetles can be picked off by hand or washed off with a strong stream of water.
-
1
Tips & Warnings
Japanese gray bark elms are tolerant of wind, drought, heat and pollution, making them a great choice for urban locations.
Japanese zelkova trees grow 50 to 80 feet tall and 40 to 50 feet wide. Site them well away from overhead lines, since pruning destroys their distinctive, vase-shaped silhouette.
References
- University of Connecticut: Zelkova Serrata
- North Carolina State University; Zelkova Serrata; Erv Evans
- North Dakota State University; Dutch Elm Disease; Robert W. Stack, et al.; July 1996
- "Manual of Woody Landscape Plants"; Michael A. Dirr; 1990
