PUMILUM

Described by Marschall von Bieberstein, Flora Taurico-Caucasica 1, 381 (1808). This species virtually remained unknown to cultivation until the year 1935 when Dr. P.L. Giuseppi led a plant collecting expedition to the Caucasus. Plants of S. pumilum were found in three widely separated localities, each from having very distinct vegetative characteristics, but with floral characters remaining fairly constant small inflorescence, individual flowers large and of a distinctive purplish-blue colour.

The following description is based on that given by Dr. Lloyd Praeger which agreees closely with that of the type form described in the Russian Flora : Rosettes are globular, about 1 to 2 cm in diameter with leaves lanceolate or oblong-lanceolate, acute or shortly acuminate, wholly green, flattish on face, convex on back, glandular-pubescent on face and back, ciliate with hairs about twice as long as pubescence. Offsets are abundant on very slender stolons about 1 cm long. Flower-stems 5 to 8 cm high, inflorescence small  about 4 to 8 relatively large flowers, petals rosy purple with pale margins; filaments purple, anthers red-purple.

In describing the forms of S. pumilum listed below we have dealt with the main distinguishing characteristics where they differ from the type plant.

S. pumilum from Adyl Su nr. 1.

This form is very similar to that described by Praeger. The rosettes are not more than 1,5 cm in diameter, pubescent, cilia stout with longer terminal hairs. In summer the rosette leaves are erect or half open and of a bright green with the outer leaves flushed yellow-green on exposure; in winter they are a dull olive-green. Culturally this is fairly easy to grow and offsets increase freely.

S. pumilum from Adyl Su nr. 2.

Rosettes much the same size as the nr. 1 form, but differing by their more ovate, blunt and very fleshy leaves that bear a denser pubescence with longer cilia. The rosettes are bright green in summer, only turning slightly pink on the fullest exposure. Culturally, not an easy plant, tends to have a weak constitution with only a few offsets given off each year, also added to this, flowers are freely produced.

S. pumilum from Armchi.

This form was collected in the northern Caucasus, S.W. of Ordzhonikidze; growing in large numbers on volcanic rock. The rosettes are apple green and larger than the type, up to 3 cm in diameter when in full growth during the summer months, but in autumn, in common with other forms of S. pumilum, the rosettes shrink down in size and change colour to a uniform brown. In summer the rosettes assume a pinkish tinge to the outer leaves on exposure, the inner leaves remaining tightly closed and the outer ones erect standing. The rosette leaves are pubescent with longer hairs on the midrib and margins, also a tuft of hairs at the apices. Flower-stems are stout, up to 10 cm high and cothed with large imbricate leaves; inflorescence usually contains 8 to 12 large flowers. Very easy of culture and multiplies freely.

S. pumilum from El Bruz nr. 1.

A very distinct form collected by Dr. Giuseppi at 3000 metres on Mount Elbruz. It is a charming plant with rosettes about the same as those of the Adyl Su forms. The rosettes are distinctly globular with very fleshy incurved leaves (even in summer), oblanceolate and glabrous except for a few scattered hairs on midrib, margins and apex. The rosettes are a deep green with the outer leaves becomming stained with light red especially so on the apex. Quite a notable feature of this form is the persistent stolons that often grow outward beneath the ground, forming new rosettes quite some way from the parent plant. The inflorescence tends to be smaller than the type with flower petals of a paler colour. Despite being collected at such a great altitude it is quite easy to grow and increases well.

S. pumilum from El Bruz nr. 2.

This form we received from Hugh F.R. Miller with the assurance that it was a plant collected by Dr. P.L. Giuseppi on Mount El Bruz.  Dr. R.S. Wale made no reference to this form when describing the various forms of S. pumilum collected in 1935 on the Caucasian expedition: Ref. Quart. Bull. Alp. Gard. Soc. Vol. 10 page 86. It is of interest to note the information in Dr. Gíuseppi’s article, “A Journey to the Caucasus” published in the Bull. Alp. Gard. Soc. Vol. 4 page 105-124; the author when making reference to S. pumilum states it varied considerably — see page 109 which appears to be quite different from any forms described by Dr. Wale.

The main characteristics are: Rosettes sub-globular, dense-leaved and of a dull green colour, the leaves are pubescent with strong marginal cilia. A notable feature is that the leaves are not incurved, but erect or half open, tight set in the rosettes with the inside leaves only a little shorter than the outside ones. The offsets are numerous and carried on short and quite stout almost decumbent stolons. Inflorescence is much smaller than the type and very few-flowered, petals are a rich purple. Cultivation is easy. 

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