8,743
edits
Changes
no edit summary
{{Inc|
Streptocarpus (Greek compound, meaning twisted fruit). Gesneriaceae. Cape Primrose. Herbs, frequently villous or lanate, adapted to greenhouse culture; choice plants, grown for the showy bloom.
Stemless, with 1 or more spreading radical lvs. or rarely with a st. and opposite lvs.: peduncles scape-like or axillary, sometimes 1-2-fld., sometimes cymose, several-fld.: fls. pale purple or blue, showy; calyx 5-parted; corolla-tube elongated, cylindrical or spreading above, limb obliquely 2-lipped, posterior lip 2-cleft, anterior larger, 3-cleft; perfect stamens 2; disk short-annular; ovary superior, imperfectly 4-celled: caps. linear, terete, splitting in 2, rarely 4 valves.—About 60 species, natives of S. Afr. and Madagascar. In Oct., 1826, there bloomed at Kew a most interesting gloxinia-like little plant, seeds and specimens of which had been collected in S. Afr. by Bowie, on the estate of George Rex, at Knysna. The plant was described as Didymocarpus Rexii. It is a stemless plant, with 1 or rarely 2 long-tubular nodding pale blue fls. on each of several short scapes, and with several clustered root-lvs. It proved to be a profuse bloomer and easy to grow. "So abundantly does it produce seed," wrote W. J. Hooker, in 1830, "that new individuals come up as weeds in the neighboring pots, and a succession of flowers may be obtained at almost every period of the year." In 1828, John Lindley made the genus Streptocarpus for this plant, calling it S. Rexii, the name it now bears. It appears to have been nearly thirty years after the intro. of S. Rexii that another streptocarpus bloomed in England. This second species was S. polyanthus, which may be taken as the type of a group that has one leaf lying on the ground and from the midrib of which arise successive several-fld. scapes. The intro. of this curious plant seems to have revived the interest in streptocarpuses, an interest that has been kept alive by the frequent intro. of other species. The chief stimulus to the systematic breeding of these plants seems to have been the intro. of S. Dunnii, said by J. D. Hooker to be "quite the monarch of its beautiful genus" (but now excelled by S. Wendlandii). Seeds of this species were sent to Kew in 1884 by E. G. Dunn, of Cape Town. It is one of the monophyllous section to which S. polyanthus belongs. In the meantime, S. parviflorus, a species allied to S. Rexii, had been intro. from the Cape region. With the three species, S. Rexii, S. parviflorus, and S. Dunnii, Wm. Watson of the Royal Gardens, Kew, set to work systematically to breed a new race of streptocarpus, and his efforts met with unqualified success. When the hybrids came to notice in 1887, the Gardener's Chronicle made the following comment on the value of the work: "The results are very striking, and we can hardly doubt that Mr. Watson has set the foundation of a new race of plants, parallel in importance to the Achimenes and Tydaeas." Several hybrid races have now been produced and several interesting species have been intro. from the wild, so that Streptocarpus seems to be destined to become a very important and popular garden genus.
Bentham and Hooker's treatment divides the Gesneriaceae into two great tribes: Gesnereae, with ovary more or less inferior and fruit a capsule; Cyrtandreae, with ovary superior and fruit sometimes a berry. The latter tribe, the species of which have been monographed by C. B. Clarke in vol. V of DeCandolle's "Monographiae Phanerogamarum," contains the genera Streptocarpus, Episcea, Cyrtandra, Aeschynanthus, Ramondia, and others. Streptocarpuses are of three groups: the stemless monophyllous species, with one prostrate leaf from the midrib of which the scapes arise (this leaf is really an enlarged cotyledon, the other cotyledon not enlarging); the stemless species, with several or many radical more or less primula-like leaves (whence the English name "Cape primrose"); the stem-bearing species, with opposite cauline leaves. The cultivated species chiefly represent the first two sections. In the American trade, four specific names chiefly occur, S. Rexii, S. Galpinii, S. Dunnii, and S. Wendlandii; but since the hybrids represent several other species, these additional species are inserted in the following account. Streptocarpus is an African genus. The stem-bearing section is confined to central Africa and Madagascar, and the others to South Africa. Clarke's monograph, 1883, describes nineteen species, but S. Dunnii, S. Wendlandii, S. Galpinii, and many others have since been discovered.
Streptocarpuses are not difficult plants to grow. They are usually raised from seeds, the seedlings blooming in eight to fifteen months from starting. The seeds are very small, and care must be taken not to cover them too deep. Give an open sunny place in an intermediate temperature. They are not stove or warmhouse plants. Of the new hybrid forms, seeds sown in February or March should produce plants that will bloom the following fall and winter; after blooming, the plants may be discarded, for better results are usually secured from new plants than from those more than one season old. The season of most profuse bloom is summer, but the bloom continues until winter. The monophyllous species can be propagated also by cuttings of the leaf. Some fanciers of Cape primroses advise propagating select types by leaf-cuttings or by division.
The following species are either little known or have not found their way into general cult.: S. Armitagei, Baker & Moore, is closely allied to S. Dunnii, differing in having a corolla much less funnel-shaped and straighter, with less spreading lobes; originally described as solitary-lvd., but 4 lvs. are said to have developed in the cult. plant. S. Afr.—S. Banksii, Lynch (S. Wendlandii x some hybrid), has 2 lvs. about 19x13 in. for the lower, the second somewhat smaller: fls. large, purple-blue. Garden hybrid. G.C. III. 56:192.— S. biflorus, Pucci, is a name appearing in horticultural journals for some unknown plant, which is said to have several blue fls.—S. bifloro-polyanthus, Duch., is a hybrid, the female parent of which is S. polyanthus, the male the above-mentioned S. biflorus: it is said to have 5 ovate-oblong, crenate, rugose lvs.; several scapes with 2-4 pale lilac fls. F.S. 23:2429.—S. Blythinii, Lynch (S. Wendlandii X S. cyaneus), has 2-5 lvs., the largest of which is 15x9 in. and another is 12 x 7 in., green beneath, in some cases reddish toward the tip, in others with the color here and there: scapes 9-10, each with 5-14 fls., about 14 in. high: fls. about 1 1/2 in. across, lavender or bluish purple; petals marked with dark purple stripes. Garden hybrid. G.C. III. 56:260.—S. cantabrigiensis, Lynch (S. cyaneus X S. Dunnii), has several lvs. which are 7-8 x 3 in.: scapes about 7 in. high, 2-12-fld., conspicuously hairy: calyx-segms. linear-lanceolate; corolla 2 in. long, about 1 3/8 in. across, tube funnel-shaped, lobes rounded, throat white with 7 deeply colored lines, limb deep rose. Garden hybrid. G.C. III.59:131.—S. Gaudinii, Hort., is offered in the trade.—S. Greenii, Hort. ex Wilson (S. Saundersii x S. Rexii), is dwarfer and more compact than the former parent, the scapes many-fld: fls. pale lilac-blue. Garden hybrid. G.C. II. 17:303. Said to be the first hybrid streptocarpus.—S. Holstii, Engl., resembles S. caulescent; plant about 1 1/2 ft. high, producing a large number of sts., each bearing 6-8 dark violet-blue fls. 3/4-1 in. long, spotted with white on the midlobe of the lower lip. German E. Afr. (Section I.) B.M. 8150.—S. hybridus. Hort., is a name applied to garden hybrids in general.—S. Kirkii, Hook. f. Caulescent; st. 4-6 in. high, stout, erect, hairy: lvs. 1-2 in. long, broadly ovate, obtuse, crenate, finely pubescent on both surfaces, base rounded or cordate; petiole 1/3-1/2 in. long: scapes axillary, very slender, 3-4 in. high: fls. drooping, opposite; calyx-lobes lanceolate, pubescent; corolla 3/4 in. long, pale lilac, tube hairy, upcurved, broad and subcampanulate, mouth expanded, lobes short rounded, ciliate, Trop. E. Afr. B.M. 6782. (Section I.) Allied to S. caulescens.—S. lichtensteinensis, Hort. (S. Wendlandii X S. Watsonii), has 2 lvs., 1 prostrate and the other smaller and erect: fls. numerous, lilac-blue. Garden hybrid.—S. Mahonii, Hook. f. Acaulescent: lf. solitary, 1 ft. or more long, flat on the ground, sessile, ovate-oblong, crenulate, tip rounded, base cordate: scapes many, crowded, densely pilose: fls. long-pedicelled; calyx-segms. pubescent, linear, corolla violet, tube 2/3 in. long, pubescent, decurved, somewhat inflated above; lobes rotundate. Brit. Cent. Afr. B.M. 7857.— S. multiflora, Laing., is a seedling of S. Rexii, with up to 30 large bluish purple fls., which have darker purple lines in the throat and running up onto the lower lip. Garden hybrid. G.C. III. 18:211; 32:327. I.H. 43. p. 67.—S. orientalis, Craib. Caulescent; st. solitary, erect, simple, 6-16 in. high, leafy: lvs. ovate to elliptic-ovate, apex obtuse, base cuneate, crenate or crenate-serrate, 1 – 3 1/2 x 3/4 – 2 3/4 in., both surfaces glandular-pilose; petioles up to 2 in. long: infl. axillary, cymose: calyx-lobes lanceolate or linear-lanceolate, white-glandular-hairy outside; corolla purple outside, paler within, tube over 1 in. long, limb about 3/4 in. across, lobes reflexed-spreading, wide oblong, tip rounded. Siam. B.M. 8526.—S. Veitchii, Hort, is offered in the trade.
}}
{{Taxobox
{{Taxobox
| color = lightgreen
| color = lightgreen