Even so few as two or three of them will give the garden a certain character which it is impossible to obtain with anything else. The following list contains some of the most suitable evergreens and evergreen shrubs.
EVERGREENS AND EVERGREEN SHRUBS VERY DWARF, FOR USE WITHIN THE ROCK GARDEN
Evergreens
The Dwarf Spruces: These are really the most useful of all the dwarf evergreens. They are now being grown much more generally, and several beside those mentioned can be obtained with little difficulty.
Dwarf Alberta Spruce (Picea glauca conica): Real, miniature spruce form; very dense growth; requires many years to attain a foot in height
Pygmy Norway S. (P. e. pygmaea): True dwarf tree form, usually less than two feet; compact, dense growth.
Dwarf Balsam Fir (Abies balsamea compacta): Best of the dwarf firs; very hardy; spreading habit of growth; like most firs, prefers moist soil.
Dwarf Mugho Pine (Pinus montana mughus): Too large for inside the small rock garden, but very variable in habit of growth, and appropriate specimens may be found by personal selection; the true dwarf form (compacta) is better for rock garden use, if specimens are selected which are not too symmetrical.
Dwarf and Low Junipers: Most of the junipers are too strong growing for the small rock garden; they will, however, stand a good bit of pruning, and for rock-garden purposes it does not matter if, as the result of this, they do not develop into symmetrical plants. The varieties which may be used include the following:
Koster Redcedar (Juniperus virginiana kosteri) : In form of growth something like the popular Pfitzer Juniper, but much smaller.
Sargent Chinese Juniper (J. chinensis sargenti): Prostrate habit; valuable especially for its good, green color.