Acaulis Group

Acaulis Group - Alpina, angustifolia, Clusii, and Kochiana, which thrive best in calcareous soils, except the last, which requires a soil free of it. In England they thrive in a way on moist soils, but flower best in the limestone soils of Ireland. They will not flower well in shade.

Tall kinds, with large roots, G. Burseri, lutea, pannonica, punctata, purpurea. These are only worth growing in botanic gardens.

Dwarf tufted kinds requiring care on the bog or rock garden, those marked * thriving in moist open soil in turf or sphagnum in full sun: the others dryer spots and pebbly soil; calcareous soil to be preferred for vernea and its forms. G. *bavarica, brachyphylla, Favrati, imbricata, phrenaica, *Rostani, *septemfida, verna.

Kinds for marshy ground:—G. Andrewsi, angustifolia, asclepiadaea, Pneumonanthe. Most of these seem of easy culture, but the American kinds gradually perish on heavy, compact soils.

Kinds thriving in leaf soil and sandy peat, with broken bits of sandstone:—G. alba, Bigelowi, ciliata, frigida, Freyniana, Froelichii, Kurroo, Parryi, pumila, Wallichiana, Weschniakowi.

Kinds of easy culture:—G. brevidens, cruciata, dahurica, decumbens, Fetisowi, Kesselringii, macrophylla, Olivieri, phlogifolia, Przewaldskii, Saponaria, scabra, straminea, tibetica, Tianschanica, Walujewi, Weschniakowi.

Annual kinds:—G. amarella, campestris, Germanica, nivalis, tenella.

These groupings are, like so many others, arbitrary if convenient. Many of the rarer kinds of Gentian come from countries little known to us, and even if we did know them the cultivation of plants is often only learned through experience, and it is common to see them thriving in conditions wholly different from those in which they grow naturally. Certain things, however, are to be borne in mind by those who aspire to cultivate Gentians, viz., that these are alpine or high mountain plants, or plants of the open breezy marsh, and that in such conditions they rarely have to do with compact heavy soils. Gritty, sandy, or peaty soils therefore suit them best—even marsh land, though saturated, is free in texture.

They grow also very often above the tree and shrub line of life, and are therefore fully exposed to the sun, and any planting of them on stuffy, half-shady conditions common in many gardens is against them, as also is the unfortunate and common practice of putting rock gardens in hollow places instead of places fully exposed to the sun. Lastly, to associate them with ferns or taller or more vigorous plants is a mistake; and, above all things, the printed lists or any other lists must not be taken to mean that the great beauty of some kinds is typical of all, as not a few Gentians are unworthy of garden cultivation. I have grown them in the most unlikely place of all, a battered wall with earth behind, and they flowered very well. The plan may be worth trying in certain soils with G. acaulis, where it fails to flower in borders.