Shade is grateful in hot summer weather, and in planting trees the fact that they will break the fierce rays of the sun in the dog days is a strong consideration with many garden-lovers.
A garden without shade is as incomplete as a garden without shelter, but there is this difference, that shade pertains rather to the comfort of human beings than that of plants. To the latter, shelter means much benefit, while shade may be inimical to them. Alpine plants, herbaceous perennials, Roses, flowering shrubs, indeed the vast majority of the most important plants, love and are benefited by sunshine.
As a rule, it is quite easy to arrange a garden in such a way that the larger trees shall not, when developed, overhang the principal plants. The point is of great importance, because the drip from trees acts adversely as well as the shade. And this raises the consideration, What plants could be chosen when existing areas under trees are bare and some ornamental planting is desired? Not every tree will need to be thus under-planted. One, at least, will be kept clear for seats, perhaps for hammocks. But there certainly are many tree-shaded places in gardens that the owner would gladly plant if he could feel certain of success.
It must be confessed at once that the number of good subjects is not great, nevertheless, it can be made to suffice. There are two really ornamental yet inexpensive evergreens which have no objection either to shade or drip: the Aucuba and the Barberry called variously Berberis aquifolium and Mahonia aquifolia. The fact that the Aucuba is often overdone, being planted in quantity on good sites to the exclusion of various beautiful subjects, must not blind us to the fact that it is a distinctly handsome plant. If it had possessed no intrinsic worth, it would never have attained to such popularity as it now enjoys. People who like variety in their gardens tend to become irritated by the repetition of one particular plant, and this may grow until it becomes an unreasonable prejudice. The Aucuba has had to endure many harsh criticisms in consequence of this feeling. It is the variegated form which is so much overplanted. The female green forms are not overdone, indeed, many people do not recognise them at sight. The habit is good, the leaves large, glossy and handsome, the berries brilliant and making a rich contrast with the leafage. Plants eighteen inches or two feet high may be planted six feet apart at any time when the weather is open from October to April, inclusive, and they will require no pruning or other cultural treatment.
As regards the Barberry, while a smaller plant than the Aucuba, it is little less ornamental, except when a winter comparison is made with an Aucuba in full berry. The habit is dense and the leaves are broad; they are deeply serrated, giving the plant a somewhat prickly appearance. The flowers are yellow and generally appear in April; they are followed by small Plum-coloured berries. The foliage becomes brownish in autumn. Owing to its dense habit and suitability for shade this plant is often planted by landowners for their game coverts, and special quotations for large quantities are made by the principal nurserymen. Those who want it as a garden plant, and have a good deal of shaded ground to cover, might vary it by using some of the forms, such as fascicularis, Moseriana, rotundifolia Hervei (or Herveyi), and undulata nana; the last is dwarf; all of these can be got from the larger nurseries. The Barberries might be planted four feet apart.
Rhododendron ponticum is a fine old species that may be planted under the lee and partly under the shade of trees. One sometimes sees large belts of it on the great estates, and remarkably effective they are in early summer, when well furnished with their massive corymbs of mauve flowers. It is, of course, evergreen, its habit is excellent, and it is very hardy. It may be planted eight feet apart. The dislike of Rhododendrons for lime must be remembered in connection with this noble evergreen.
The next most important plant for shade is the Holly. If small plants are put in four feet apart, either in early autumn or late spring, they will generally establish themselves and thrive. They may not grow into such handsome specimens, nor berry so freely, as in the open, but they will be ornamental. There are many beautiful garden varieties of Holly, but none is better for shade planting than the Common.
Privet is so largely used as a hedge plant that a suggestion for using it singly or in groups may surprise the reader, nevertheless, it is by no means a bad shrub. When grown in a hedge and left unshortened it is gawky and ugly, as the plants "draw" up and become bare at the base, but this is not likely to occur when it is given room, and in any case can be corrected by pruning back once or twice. The oval-leaved species, known botanically as Ligustrum ovalifolium, should be chosen. An advantage of this shrub is its liking for poor limestone soils.
The foregoing will probably meet the wants of most readers as far as the larger shrubs are concerned.
One of the best of the smaller kinds is the Butcher's Broom, Ruscus aculeatus. It is not a strikingly handsome plant, but it will grow almost anywhere and is evergreen. Another good small shrub is Gaultheria Shallon, an evergreen belonging to the Ericaceae, but fortunately not so exacting for a peaty soil as most of the members of that order are. It will thrive in sandy soil, or indeed in any fairly fertile moist garden soil. It bears white flowers in spring and berries follow. There is a garden form called acutifolia. Both the Butcher's Broom and the Gaultheria may be planted two feet apart.
The two best running plants for carpeting ground under trees are the Periwinkles, Vinca major and V. minor, and common house ivy. The Periwinkles are generally preferred, because their large blue flowers are attractive. There are several garden forms of Vinca minor, one with white flowers (alba) and another with double blue flowers (caerulea flore pleno), one with silver variegated and another with yellow variegated leaves. The silver-variegated form is particularly pretty. The Periwinkles may be planted a foot apart.
The new Chinese shrubs Sarcococca ruscifolia and humile will prove an excellent addition to the shrubs which thrive in shade. S. ruscifolia is the better of the two. It is a vigorous shrub of good habit with green leaves. Pachysandra terminalis is aso a good shade shrub.