Zelkova: a noble landscape tree

Flower & Garden Magazine, Dec-Jan, 1993 by Cathy Sabol

Thank Heaven I Didn't Search alphabetically for a versatile shade tree for my barren new yard. It would have taken me forever to pass "ash," "birch" and "catalpa," to finally come upon "zelkova." But as I analyzed potential trees for their growth rate and habit, predicted longevity, tolerance to urban stress and resistance to pests and diseases, the Japaneses Zelkova serrata kept popping up.

The zelkova's fan-shaped silhouette and oval, serrated leaves resemble those of the American elm and make it good substitute for this once-favored stately tree. In fact, zelkova is a member of the elm family, but the most significant difference between the two trees is that the zelkova is resistant to Dutch elm disease. The bark-feeding beetles that transmit the fungus to its American cousin avoid feeding on this Japanese counterpart.

Although introduced into the United States from Japan in the early 1870s, the zelkova still lacks the name recognition and popularity of more familiar trees like maples and poplars. Even so, more and more gardeners are discovering the zelkova because of its many fine quantities. Its wide-spreading canopy and graceful form are sure to sway gardeners looking to plant a shade tree. Additionally, the zelkova features interesting beechlike gray bark and attractive fall foliage in colors ranging from yellow to orange, dark red and reddish brown.

The zelkova is an adept city dweller, suitable for planting in back yards, along neighborhood streets and boulevards and in parks. Although this tree needs full sun, it is impervious to the ravages of smog and strong winds and is hardy in Zones 5 through 8. Zelkova also provides quick shade, often doubling its height in four to six years, eventually reaching 60 to 90 feet. Poor soil doesn't seem to bother it as long as the soil is well-drained and within the pH 5.5 to 7.5 range.

The zelkova is readily propagated from seed but seedling plants of the species vary dramatically in form, growth rate and fall color. Several cultivars have been selected that exemplify the best of the breed, displaying uniformity of shape, rapid growth and superior fall color.

|Halka,' recent cultivar, is faster growing and more elmlike than previous varieties. |Village Green' producers a good vase-shaped form and is highly disease resistant. Virtually identical is the variety |Green Vase,' although the latter doesn't grow as tall and reaches maturity with a smaller crown. All varieties need careful training and pruning to develops strong frameworks.

Next time you visit your local nursery, take a look at their zelkova stock. For my money, zelkova is more than just an elm replacement - it is my candidate for a favorite ornamental shade tree.