This section is from the book "Sub-Alpine Plants Or Flowers Of The Swiss Woods And Meadows", by H. Stuart Thompson. Also available from Amazon: Sub-Alpine Plants: Or, Flowers of the Swiss Woods and Meadows.
Plant covered with whitish, silky tomentum. Stems 10-18 inches high, erect, simple. Leaves oblong-lanceolate, acuminate, the upper ones narrower. Flowers deep pink, crowded. Petals deeply divided. Calyx coriaceous, with 10 prominent nerves and broadly acute teeth. Capsule oblong-acute, with five teeth, much shorter than the carpophore.
Sub-alpine pastures and broken ground. June to August.
Western and Southern Alps, Southern Switzerland, Italy, Tyrol.
A taller plant, covered with dense white silky tomentum. Leaves oblong-lanceolate, acute. Flower solitary, axillary, and terminal, large and handsome, reddish purple, or rarely white, longly petioled in a loose, dichotomous spray. Calyx with 10 unequal nerves and linear teeth, much shorter than the corolla. Petals entire or slightly crenate. Capsule oblong-acute, without carpophore, 5-toothed.
Wooded hills and rocky, bushy places in the plains and sub-Alps. Reaches a considerable height in Val Tournanche and the Saas Valley. May to July.
Southern Europe from Portugal to the Caucasus; probably only in Valais in Switzerland, except where it has escaped from gardens, it being a favourite plant in cottage gardens, as in England.
Calyx, corolla, and stamens as in Lychnis. Styles 3. Capsules opening at the top in 6 teeth or short valves. A very large genus, of about 25b species, widely spread over Europe, Central and Northern Asia and N. America, with a few species in S. Africa.
Usually stemless or with stems 1/2 to 1 inch high.
Root woody, branched, with many aerial shoots, covered with the withered leaves, and bearing a rosette of fresh leaves forming dense, cushion-like tufts. Sometimes hemispherical masses a foot across are seen covering rocks or grassy ground in Alpine pastures. Leaves radical, linear, acute or acuminate, entire, shortly ciliated, otherwise glabrous. Flowers dioecious or hermaphrodite, solitary at the extremity of the shoots. Calyx cylindrical, or bell-shaped, with 10 nerves; teeth ovate, obtuse. Petals obovate, lanceolate, rose-coloured, slightly emarginate.
Rocks and pastures in the Alps; common, 5000-11,000 feet. May to July.
Carpathians, Eastern, Central, and Western Alps; Pyrenees, British Isles, Arctic Europe, Asia and America; Iceland, Spitzbergen. Rocky Mountains of Canada.
There are two varieties which grow in the Alpine zone only:
Var. exscapa DC, a stemless, small form with lighter pink flowers, and Var. elongata DC, a rare form with longer stems than in the type, larger flowers, and a looser habit.
Though a shy bloomer in this country, Silene acaulis is a very useful rockery plant. It should have plenty of sun, and a poor, gritty soil, or it will make too much soft green growth, which gets cut off in winter. It may be wedged between stones in crevices of rock.