When misty trade-winds dump their cool gray fogs over the Golden Gate during midsummer, that is the time when the Lily-of-the-Valley Tree adorns itself with myriads of small ivory white bells that toss their perfume on the air as the boughs play with the breezes. Having practically no competitors among flowering trees at that time of the year, this lovely immigrant from the Madeira Islands seems so pleased at having been welcomed in California that it clothes itself in cascading sprays of beauty in gratitude for being here.
Named as one of the “garden aristocrats” by the late Ernest H. Wilson, this species of Clethra is a distant relative of the native California Madrona Tree, and like this, it grows to a round headed shape up to 15 feet, but also has a tendency to become bushy and shrub like. It can be shaped into a clean limbed standard, but since its boughs taper to plume like sprays, it looks just as handsome when permitted to have its own sweet will, without benefit of the pruning shears.
Clethra arborea, as it’s called, has glossy, lance like foliage, so evergreen the year round that this alone is an eye treat. It is a member of the Heath Family and like all of them, it likes a cool, moist climate and a lime free soil not as much on the acid side as for Rhododendrons and Camellias. In Golden Gate Park, San Francisco, where a number have been thriving for several years, they do with a minimum of care, apparently asking for nothing but to be left alone. They are hardy down to 28 degrees F. If frosts should happen, the tender growth is sacrificed but the roots send up new shoots at once, but a year’s crop of flowers is skipped.
For its first few years, young plants can be left in wooden buckets in which they will flower prodigiously. Grown in such containers, small specimen trees are sometimes used as ornamentals at weddings where their lace like flower sprays are a stand in for Lilies-of-the-Valley, usually so scarce during the dog day weeks. Their perfume reminds one of something delectably good to eat. As cut flowers, Clethras hold up far better than the fragile Lily-of-the-Valley. As material for flower arrangements the boughs are most useful as the daintiness of the flowers is a flattering background for blending colors.
“Cuttings of half ripe wood root so readily that no special skill is required for the propagation of this handsome shrub.,” according to Victor Reiter Jr., who grows numerous Clethras in his garden beside Sutro Forest, San Francisco. It is also propagated by layering, divisions and by seed which it sets in profusion. It is remarkably disease-resistant in this zone, but does not do so well in the hot, dry interior of the state. If grown away from a coastal climate, Clethra trees require frequent overhead mist spraying. In dry climates, they are also subject to scale. But this can be combated by the usual chemical sprays used to clean garden shrubs of this pest.
The flowering season lasts for nearly two months. When not in bloom, the Lily-of-the-Valley Tree presents a clean, leafy heartiness that imparts interest to any fine garden; especially those located where fogs and summer winds do havoc with more tender plants. Yet for all its raggedness, this tree has an air of captivating beauty, especially when it’s fragile blooms veil it in white mists
By LOUISE WEICK