Alpine Plants.

Perhaps a formal rockery, or a special alpine garden, may seem altogether too ambitious for a school-garden. Still, the New Zealand mountain-plants yield such instructive material for study, and are so beautiful or curious, that a few, at any rate, should be grown; and there is usually some shady corner that might be spared for these plants. Also, a good deal can be done in the way of providing a suitable growing-place by the aid of a few bricks or stones, especially if there be an abundant water-supply.

Of all forms of flower-gardening, this growing of alpine plants is the most fascinating. During recent years the alpine garden has become firmly established in Europe as an indispensable part of any garden of note. In scientific establishments, too, the cultivation of alpine plants is pursued with vigour. The new Botanic Gardens of Berlin have a great rockery, arranged on plant-geographical principles, to represent the different alpine floras of Europe. Some day, when we in New Zealand have what we ought to possess, a national botanic garden, it may there be possible to reproduce the different plant societies of New Zealand. The Royal Botanic Gardens of Edinburgh have the finest collection of alpine plants in Britain, and are specially rich in New Zealand species. Many of the Continental universities have their alpine gardens high in the Alps, where the effect of an alpine climate on the form and structure of plants can be studied.^*

As for growing New Zealand alpine plants, the method entirely depends upon the climate of the locality. At Invercargill, in many parts of Dunedin and its environs, on the west coast of the South Island, and probably at many places in the interior of the North Island, alpine plants can be grown with the greatest ease in the ordinary flower-border, any special construction, such as a rockery, being quite superfluous for many species. But in some parts of New Zealand, and in certain soils, it is quite otherwise. The grand secret of growing New Zealand "alpines" is to give them perfect drainage, a shady but quite open position, and plenty of water. Where the drainage is absolutely perfect, it is hardly possible to overdo the watering page 173

Fig. 68.—Alpine Vegetation of Tongariro. Gentiana bellidifolia in bloom. A natural Rock-garden.
Lands Department.] [Photo, L. Cockayne.

page 174in a dry climate. In a wet one the natural rainfall may be enough. To procure this good drainage, in many cases a rockery is useful (fig. 68). It is also a fact that some few plants which root deeply love to press their roots far between the stones; and, finally, a raised bed is advantageous for displaying the smaller plants. As for the rock, some kind that will crumble with the weather is the best; but bricks are far from being a bad substitute, although an ugly one. As well as stone, there must be plenty of light soil. Sweet, peaty soil is good; a foundation of small stones is also excellent. Each individual

Fig. 69.—Viola Cunninghamii, the common New Zealand Violet.
[Photo, J. Crosby-Smith.

plant should be allowed a fair proportion of soil. Small shrubs, planted here and there, are effective, giving both a natural appearance and affording shelter. In eastern Canterbury the nor'-wester is the bane of the alpine gardener. The sou'-wester does little harm, but the constant east wind is better blocked out.

With management, nearly all the New Zealand alpine plants can be grown; but some are difficult to manage, even in the most favourable gardens. The following are some of the easier-grown of the page 175

Fig. 70.—Cotula pyrethrifolia, growing on a shingle-slip. Southern Alps, Westland.
[Photo, L. Cockayne.

page 176herbaceous plants: Ranunculus insignis, R. lobulatus, R. Enysii, Viola Cunninghamii (fig. 69), Oxalis magellanica, Geum parviflorun, Epilobium gracilipes, Myosotis australis, M. decora, Cotula pyrethrifolia (fig. 70), Raoulia australis, R. tenuicaulis, R. subsericea, Acaena microphylla, A. glabra, Ourisia macrophylla, Celmisia verbascifolia, C. rigida, C. Lindsayi, C. Mackaui, C. coriacea, C. spectabilis, Angelica Gingidium, Brachycome Sinclairii, Helichrysum bellidioides, Gnaphalium trinerve. The following are small, shrubby plants: Carmichaelia nana, C. Monroi, Veronica epacridea, V. loganioides, Rubus parvus, Veronica Gibbsii, Coprosma repens.

Any of the taller subalpine scrub plants can be used, and can be replaced by smaller specimens when they get too big. In fact, the plants to be made use of will depend so much on the size and situation of the alpine garden that hints regarding what to grow are not of much use. Moreover, the enthusiastic collector will bring home all sorts of plants, regardless of their capabilities, and the success of the alpine garden will be due entirely to his own energy, and to the knowledge he will acquire in the school of experience.