This section is from the book "The Standard Cyclopedia Of Horticulture Vol2", by L. H. Bailey. See also: Western Garden Book: More than 8,000 Plants - The Right Plants for Your Climate - Tips from Western Garden Experts.
(Koloutea, ancient Greek name). Leguminosae. Bladder Senna. Shrubs grown chiefly for their attractive yellow or brownish red flowers and the ornamental bladder-like pods.
Deciduous, with alternate, odd-pinnate leaves: leaflets many, rather small; stipules small: flowers papilionaceous, in axillary, few-flowered, long-peduncled racemes, yellow to brownish red; calyx campanulate, 5-toothed; standard suborbicular with 2 swellings above the claw; 9 stamens connate, 1 free: pod inflated, bladder -like, many-seeded. - About 15 species in the Medit. region to Abyssinia and Himalayas. Ornamental free - flowering plants of rapid growth, with pale green or glaucous foliage and yellow or brownish red flowers during summer, followed by large, usually reddish-colored and decorative pods. They grow in almost any soil, but prefer a tolerably dry and sunny position; not quite hardy N., the hardiest being C. arborescens. - Prop, by seeds sown in spring or by cuttings of mature wood inserted in fall in sandy soil; rarer species and varieties are sometimes grafted on C. arborescens in spring under glass.
a. Flowers yellow: pod closed at the apex.
Linn. Fig. 1040. Shrub, to 15 ft.: leaflets 9-13, elliptic, dull green, mucronulate, usually slightly pubescent beneath, 1/2-1 in. long: flowers 3-8, about 3/4in. long; wings nearly as long as the keel, flat. June-Sept. S. Eu., N. Africa, N. B.M. 81. - Leaves have cathartic properties. variety crispa, Kirchn. Dwarf, with crisped leaves variety bullata, Rehd. (C. bullata, Hort.). Dwarf and compact: leaflets 5-7, obovate or nearly orbicular and somewhat bullate.
Fig. 1040. Colutea arborescens.
Boiss. (C. longialata, Koehne. C. melano-calyx, Hort., not Boiss.). Shrub: leaflets bluish green, usually 11, oval or broadly ovate, rounded or truncate and mucronulate at the apex, 1/2- 3/4in. long: flowers bright yellow, 3-6, about 3/4in. long; wings longer than the keel. June-Aug. Asia Minor. G.C. III. 16:155.
AA. Flowers orange-yellow or brownish red; wings shorter than the keel.
Willd. Shrub, to 10 ft.: leaflets 7-13, obovate, grayish green or glaucous, 1/3_ 2/3in long, nearly glabrous: flowers 3-6, orange or reddish yellow, the standard with brownish markings: pod closed at the apex. June-Sept. - Probably hybrid of garden origin between C. arborescens and the following, often cult, under the names of the following species.
Mill. (C. cruenta, Ait.). Shrub, to 6 ft.: leaflets 7-11, obovate, glaucous, thickish, 1/3- 1/2in. long, nearly glabrous: flowers 3-5, reddish yellow or brownish red: pod open at the apex. June-Sept. S. E. Eu., Orient. - Often cult, under the name of C. hale-pica or C. istria.
C. brevialdta, Lange. Shrub, to 4 ft.: leaflets usually 11, oval, 1/2-3/4in. long: flowers 2-6, yellow; wings much shorter than keel. S. France. - C. gracilis, Freyn & Sintenis. leaflets usually 11, obovate, 1/4-1/3in. long: flowers 2-5, yellow, with the wings almost as long as the keel. Turkestan. - C. istria, Mill. (C. halepica, Lam. C. Pocockii, Ait.). To 4 ft.: leaflets glaucous, small and numerous: flowers yellow, nearly 1 in. long; wing longer than the keel. - C. nepalensis, Hook. Similar to C. arborescens: racemes drooping. B.M. 2622. B.R. 1727. Tender.