Plants that glow in the dark corners of the garden

This week, white flowers and variegated foliage bring light into the shadowy edges of my landscape.

A variegated Japanese anglelica tree (Aralia elata ‘Variegata’) looks almost white against the dark wooded background. And shade-tolerant woodies like Japanese clethra (Clethra berbinervis), bottlebrush buckeye (Aesculus parviflora), and Annabelle smooth hydrangea (Hydrangea arborescens ‘Annabelle’ produce ample white flowers for a similar lightening effect.

For years, I never had flowers on ‘Annabelle’ (see second photo above), a cultivar of a shrub native to the Eastern US, because deer nibbled the shoots before it bloomed. But the plant didn’t die. It just suckered and grew.

In the past few years, marauders have left it alone. Now giant snowballs cover the shrub, which has expanded to about 3 feet high and four or five feet wide. Flowers grown in the shade are smaller than those grown in the sun, but they still look plenty big to me.

Japanese clethra (see first photo above) looks more exotic, with its angled clusters of sweetly fragrant white flower spikes, dark green leaves, and exfoliating gray and brown bark. Mine is about 10 feet high with an open habit typical of shrubs and trees grown in shade.

For season-long brightness, however, you can’t beat the variegated Japanese angelica tree. (See photo at right.) The tiered branches show off white-edged leaves to maximum effect. We’ve had ours for several years. It grows slowly, but the layers were evident early on.

One of the best specimens I’ve seen is at Longwood Gardens in front of the entry pavilion. In fact, most of the plants mentioned in today’s post first came to my attention at Longwood Gardens, an institution that opened my heart and mind to the wonder of woody plants. If trees and shrubs intrigue you, this public garden is a worthy destination.

Penelope O’Sullivan, who writes about trees and shrubs at Diggin’ It, is the author of “The Homeowner’s Complete Tree & Shrub Handbook: The Essential Guide to Choosing, Planting, and Maintaining Perfect Landscape Plants.” She has a landscape design business on the New Hampshire seacoast.

Editor’s note: To read more by Penelope, check our blog archive. For more Monitor gardening, see our main gardening page and our RSS feed.

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