The Light and Dark Side : Solving the Dilemma of Planting Against a North Wall

The letter, referring to a recent article on camellias, begins: “The sentence ‘They are one of the few shrubs that thrive in a winter-shade, summer-sun situation’ caught our attention. On our small patio, our winter plants languish in the summer, and the summer ones suffer in the winter. So, can you perhaps name any other plants that can stand these extremes? We’d prefer flowering ones but would settle for anything.”

Theirs is not an uncommon problem. Almost every north wall is subject to this summer-sun, winter-shade dilemma. When the sun sweeps low on the horizon in winter, shadows double and then triple in length; when the sun climbs high in summer, the same plants that grew in total shade are plunged into the hottest sunlight of the year.

In the warmer interior valleys, the best solution is probably an overhead lattice that can be removed in winter, then put back on for summer, so the plants are always in the shade. But for most parts of town, there are many plants that can stand both extremes.

Camellias top the list; there is good reason that they line so many north walls. They should be made the backbone of a summer-sun, winter-shade planting, not only for their flowers but also for their glossy, dark-green foliage (though it may yellow a bit in the summer sun).

Another old-timer seen along north walls is hydrangea. Dormant in winter, or nearly so, it looks best in front of evergreen plants, such as camellias. It blooms in early summer, long after camellias do, when color is scarce. The leaves are at least double the size of camellias’ and a much lighter green--a pleasant contrast. If you don’t care for the huge pompon flowers, look for the graceful lace cap hydrangea. Weidners’ Begonia Gardens in Leucadia sells a lace cap especially suited to Southern California.

Yesterday-today-and-tomorrow ( Brunfelsia pauciflora ‘Floribunda’) is a camellia look-alike--from a distance, anyway--but the flowers are purple, changing to lavender and finally fading to white. Put it right up against the wall where it will get the least sun, and treat it like a camellia. But be patient; it grows slowly.

While you’re waiting for camellias and brunfelsia to grow, try fast-growing, free-flowering abutilons. Sun or shade, it doesn’t seem to make much difference to them. With leaves resembling maple and with their bell-shaped flowers, they’re very pretty and graceful shrubs--for the first few years. In time, they become woody and look rather weedy, though they continue to flower most of the year. With a little searching, you can find bright reds, soft pinks, apricots, yellows and a pure white.

The perfect companion for abutilons is low-growing Japanese anemone. It may be difficult to tell where one plant begins and the other leaves off--their foliage is similar--but anemones seldom grow taller than two or three feet. The flower spikes, though, can shoot up to four or even five feet, and they come in the late summer when the abutilons are least likely to be in bloom. The flowers are pink, lavender or, most often, white.

For foliar contrast (something not often enough sought after in garden plantings), try an azalea named ‘Little John,’ which has deep reddish-purple leaves. Azaleas, of course, after camellias, are the plants seen most often in sun-shade situations. Eupatorium coelestinum , rarely called by its common name of mistflower, has deep reddish-purple foliage too, only the leaves are large, about four to five inches long. The flowers bloom in winter or spring and look like fluffy ageratums, light violet in color. It is not a common nursery item (try Desert to Jungle Nursery in Montebello), though it’s easy to grow.

If you want that north wall simply to disappear, plant Boston ivy ( Parthenocissus tricuspidata ) against it. This deciduous vine clings tightly to any surface and prefers the north wall of a house, making a glossy green backdrop for other plants.

That would be my list, but I’ll gladly accept any other nominations for this difficult position in the garden.