A dwarf, evergreen shrub growing 4 to 10 in. high in gardens; stems erect, much-branched, quite hidden on the younger parts by closely overlapping leaves. Leaves 1⁄6 in. long, arranged in four rows, so as to give the leaf-clothed stem a four-angled shape; stalkless, concave in front, each one closely appressed to the leaf above it; furrowed behind, slightly downy. Flowers sparsely borne at intervals along the younger parts of the stem during April and May, and produced singly from the leaf-axils. Corolla nodding, white tinged with red, bell-shaped, 1⁄6 to 1⁄4 in. long (occasionally longer), calyx of five ovate divisions, green tinged with red; flower-stalk decurved, about four to six times as long as the leaves. Bot. Mag., t. 3181.
Native of the northern hemisphere, in Arctic and sub-Arctic regions; said to have been introduced from Lapland in 1810, and later from N. America. It differs from C. fastigiata in the smaller flowers, and in the leaves being without the silvery membranous margins, although slightly ciliated.
var. saximontana (Small) Hitchcock C. tetragona subsp. saximontana (Small) Porsild. – Pedicels not more than two or three times the length of the leaves and often scarcely exceeding them, so that the flowers nestle against the leaves. As to the size of the flowers, they appear to be of about the same length as they normally are in the typical variety of C. tetragona (about 1⁄5 in. long). A native of British Columbia, Alberta and S.E. Yukon; described by Small (as a species) from plants found by him on the summit of Mt Sulphur, near Banff.
C. (tetragona × fastigiata) ‘Edinburgh’. – This very free-flowering hybrid arose spontaneously in the Edinburgh Botanic Garden and was given an Award of Merit in 1957. The plant shown was about 7 in. high and 12 in. across and bore up to twelve open flowers near the tip of each stem.