Ivory Silk Japanese Tree Lilac

There is much more to lilacs than those big bushes with blue or purple flowers that granny used to grow. Japan has sent us loads of great garden trees and shrubs, but the Ivory Silk Japanese Tree Lilac really is one of the most outstanding. There are few if any flowering trees for smaller gardens that can easily be grown as a specimen with other plants beneath them, but this is one, so you won’t lose a lot of garden space with this tree, just raise your garden beauty to higher levels. There are also few flowering trees, especially in colder zones, that look so good even when not in bloom, or ones that keep their blooms for so long. The fluffy, creamy-white flower heads make a gorgeous display, the leaves are always clean and handsome, and the bark in winter is outstanding. All in all this really is a fabulous choice, even if fashion has apparently dictated that we should plant something else. If you live in cooler zones and want simple but striking beauty, then our answer to that fashion advice is ‘forget it’. Go ahead and plant, you’ll be glad you did.

Growing the Ivory Silk Japanese Tree Lilac

Size and Appearance

The Ivory Silk Japanese Tree Lilac is a large shrub or small tree, reaching 20 to 25 feet in height, with a spread typically 12 to 15 feet wide. The branches rise somewhat vertically, so that the crown stays high, without sweeping down to the ground. The trunk and stems have smooth, glossy reddish-brown bark when younger, turning a little rougher and grayer with age. There are prominent horizontal bars on it, in a pale tan color, called lenticels, which give it a look similar to the bark of a cherry tree. The twig structure is upright to horizontal, with attractive zig-zags, making the winter profile very attractive and appealing. The leaves are large, between 3 and 6 inches long, and broad ovals tapering to a pronounced tip. They are dark green, with a slightly satiny surface. In fall, especially in cold zones, they turn a lovely clear yellow color, staying more greenish-yellow in warmer areas or in shade.

Flowering happens in June, after the main rush of spring blooms, and it is always profuse, reliable and very showy. The tiny, ¼-inch flowers are carried in hundreds of not thousands in big conical clusters between 8 and 12 inches long. They are a lovely creamy-white color, fragrant with the scent of honey, and have a light, fluffy look. A tree in bloom is very, very attractive indeed. It’s also attractive to pollinators, butterflies and even hummingbirds, who all show up for a sweet nectar party. Flowers are followed by clusters of seed pods which are pleasant, but not showy, adding a little something in fall after the leaves drop.

Using the Ivory Silk Japanese Tree Lilac in Your Garden

The high branching structure of the Ivory Silk Japanese Tree Lilac makes it simple to maintain good clearance beneath this tree, and it’s one of the very few smaller flowering trees where you can do this so easily. That makes it perfect for a lawn specimen in a smaller garden, because you can easily pass underneath, and keep the lawn growing. In beds it will provide shade that allows you to grow smaller shrubs underneath, and it is also lovely tucked into the angles of walls around your home, used as a boundary screen or avenue, or in front of natural woodland. It’s ideal, and appropriate, when you want a background tree for an Asian-style garden.

Hardiness

No wonder this is a top-choice tree in colder zones, because it is completely hardy and a very reliable flowering tree in zone 4. It also grows well into zone 7, growing best in areas that have definite winter weather, including the northeast and the upper Midwest. It doesn’t grow so well in the southeast, with hot, humid summers, and in the northwest it may not get enough of the summer sunshine it loves.

Sun Exposure and Soil Conditions

Although it will take a few hours of shade each day, full sun will give you the best results with this tree. It grows vigorously and well in almost all soils that are well-drained, especially, but not exclusively, in slightly acid soils that are rich and reasonably moist. It has great tolerance of urban soils, and it’s a terrific tree for town gardens. Avoid wet soil and very dry, sandy soils.

Maintenance and Pruning

Unlike old-fashioned French lilacs, you won’t see powdery mildew making the leaves unsightly in summer, and neither will you be troubled by the nasty lilac borer. It stays generally free of pests or diseases. If you want a tree, with a single stem, or with just two or 3 stems, prune off side branches while the tree is young, to avoid scars. Trim up as needed, or keep it as a rounded shrub with lower branching. Little or no pruning is needed, but if you do need to trim or remove branches, do it straight after flowering is over. When young it pays to remove spent flowers, saving that energy needed for seeds and channeling it into growth and next year’s flowers.

History and Origin of the Ivory Silk Japanese Tree Lilac

The Japanese tree lilac, Syringa reticulata, arrived in North America from the hills of Hokkaido, the northernmost island of Japan. It was brought over by Charles Sprague Sargent, head of the Arnold Arboretum, Harvard University, in 1876. It was sent to Europe from there a decade later. There are specific other forms of this tree found in China and in Korea. The variety called ‘Ivory Silk’ is a seedling selected by Sheridan Nurseries, Ontario, Canada for its more compact, neat form. It was introduced in 1973.

Buying the Ivory Silk Japanese Tree Lilac at the Tree Center

This tree has been the winner of multiple awards for its garden and landscape value, including the Pennsylvania Horticultural Society’s Gold Medal in 1996, and the Theodore Klein Plant Award of the University of Kentucky Nursery & Landscape Program in 2000. Why experiment with new, unproven trees when this one has such a great track record? Go with the best, and plant an Ivory Silk Japanese Tree Lilac today. Order now, it often isn’t available from many nurseries anymore.