The Golden State: Where & How to Live, Secure, Visit, Enjoy and Thrive in California
American Rock Gardens
Rock Shrubs
ENTHUSIASTS in rock gardens are always eloquent over tiny little perennial herbs of no stature at all. Yet many little rock plants are truly shrubs. Why not use more shrubs in a rock garden? Why not even build a rock garden wholly of shrubs? Such a planting would have its interest throughout the year; but nothing like this has been attempted.
The characteristics of shrubs well suited for the rock garden are not well understood. The height should be not over one or two feet, to be in scale with the details of the construction and the herbaceous planting, save at certain points a shrub of larger stature is used as accent or to mark transition to another section of the scene. But such plants as Irish Juniper and Magnolia steUata are too suggestive of the formal garden or well-trimmed lawn, and have no relation to alpine peaks.
Their root systems should go deeply into the bank, that dry seasons or pulling frost may not harm them. Pretty little Daphne has not much root and is rather useless, as some extreme of climate is sure to take most of the life out of it frequently.
Of course, some special beauty of flower, fruit, or foliage is expected, but most important for a rock garden is depressed or irregular shape suggesting the force of the winds upon the branches, and barren soil stunting the growth. Any shrub which grows freely should be excluded. Horticultural forms of dwarfed and stunted nature may be used, partly because they are uncommon and of unusual shape, but more because they reflect the restraining powers of nature.
FIG. 7.—SHRUB AND ROCK
But most shrubs in a rock garden get too large and crowd out the perennial plants. There is a scarcity of small shrubs; yet there are sufficient in cultivation to make a good showing.
The following are, as a rule, perfectly hardy in the winters of Boston in conditions of a wellbuilt rock garden. For a wanner climate this list would be much longer.
