As this species requires what is called cool treatment very little expense need be incurred in its cultivation. Indeed, any one having a small house where a temperature can be kept up in winter of from 45° to 50°, with as little fire-heat as possible, can grow a great quantity of them, since they occupy but little space. In summer no fire-heat is required, unless the nights are cold, which is seldom the case at that season, but no draughts should be allowed to reach them, as draughts are as deleterious to them as to all other plants grown in glass houses. They require shading from the scorching rays of the sun, but like to have all the light that can be given them. Under this treatment they will grow stronger and stronger, and flower more and more freely.
The potting material which we find most suitable for them is good fibrous peat, with the finer earthy particles shaken out; they must have good drainage, in fact the pots must be three-parts filled with drainage material, and the plants well elevated above the pot rim. They are naturally free-rooting plants, but we find a little live sphagnum moss on the top of the peat causes them to root more freely, and as they require a good deal of moisture at the roots during their period of growth, the moss, if kept in a growing condition, will help to supply their wants.
PL. 48. VANDA CŒRULESCENS.
VANDA CŒRULESCENS.
[[Plate 48].]
Native of Burmah.
Epiphytal. Stem one to two feet high or more, producing long stout flexuous roots from the leaf bases. Leaves close set, distichous, linear-ligulate, truncately-bilobed, coriaceous, channelled, five to seven inches long, of a deep green colour, carinate, the keel forming an angular projection at the tip. Scapes or Peduncles slender, distantly vaginate, with small appressed sheaths, axillary, erect, bearing a ten to twenty flowered raceme longer than the leaves. Flowers neat and very pleasing, pale mauve-blue; sepals incurved, cuneate-ovate, obtuse, clawed, of a pale greyish blue; petals similar in size, form, and colour, twisted at the base, with the two lateral lobes tawny-yellow, and adnate to the column, the middle or front lobe obcuneate dilated and emarginate at the apex, the margins deflexed, of a rich violet-blue, with a pair of keel-shaped deep violet calli and a short intermediate one on the disk, the spur straight or incurved, conical, tipped with green. Column small, blue.
Vanda cœrulescens, Griffith, Notulæ, 352; Id., Icones, t. 331; Lindley, Folia Orchidacea, art. Vanda, No. 19; Reichenbach fil., in Walpers’ Annales Botanices Systematicæ, vi., 868; Id., in Gardeners’ Chronicle, 1869, 498; 1870, 529, fig. 97; Hooker fil., Botanical Magazine, t. 5834 (colour faulty); Williams, Orchid Grower’s Manual, ed. 5, 305.
The Vandas are a most noble family of Orchids, including amongst them many beautiful species, such as V. suavis, V. tricolor, V. Batemanni, and others. They are well furnished with leaves, and make splendid specimens, requiring considerable space in which to grow them, but they are plants of great beauty, and when not in bloom make grand objects of attraction. No collection should be without them, as they flower at all times of the year. Where a number of these Orchids are grown, as at Chatsworth, we have seen as many as 193 spikes in blossom at one time, presenting a most glorious sight.
The Vandas are of easy cultivation. The species which we now figure is a small, elegant-growing, free-blooming plant, and also very distinct in character, as will be seen from the plate, which gives a good representation of it. Our drawing was taken from a beautiful specimen growing in the splendid collection of C. Dorman, Esq., The Firs, Laurie Park, Sydenham, who has one of the best grown collections of Orchids we have seen, and one which does great credit to Mr. Coningsby, the gardener.
Vanda cœrulescens is a compact growing species, as may be seen from our plate. In this instance it produced a flower spike of a drooping habit fifteen inches long, which is quite an exception, as the flower spikes are generally more or less erect or ascending. The sepals and petals are of a bluish-mauve, the lip of a deep blue. It is altogether most distinct in colour, and a plant that is greatly required in a collection of Orchids for the sake of the charming contrasts it yields. It blooms at different times of the year, and continues for several weeks in beauty. We find the heat of the East India house is congenial to it. It grows well in sphagnum moss, and must have good drainage, because it must be kept moist during the growing season; when at rest less moisture is required. The plant thrives either in a pot or in a basket suspended from the roof, so that it may get plenty of light, but must be shaded from the sun.