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.
(Greek, rattle, castanet; from the rattling of the seeds in the pod). Leguminosae. Rattle-Box. Annual outside herbs, and shrubs grown in greenhouses or in the open far South.
Herbs or shrubs of various habit: leaves simple (actually unifoliolate) or compound: flowers in terminal racemes or rarely the racemes opposite the leaves; calyx-tube short, the teeth narrow, as long as or a little shorter than the pea-like corolla. - A cosmopolitan genus of perhaps 250 species, in tropics and sub-tropics mostly. For best results, the seed should be started early indoors, after being soaked in warm water. The name is sometimes misspelled Crotolaria. Greenhouse kinds are subject to red spider. C. juncea yields the Sunn hemp of India. Our common rattle-box, C. sagittalis, is often a troublesome weed.
a. Leaves apparently simple.
Linn. Annual, 1 1/2 ft. high: branches few, short: leaves entire, very various in shape, but typically obovate with a short mucro, clothed beneath with short appressed hairs: flowers about 12 in a raceme, yellow, streaked or blotched with purple; standard roundish, notched. Cosmopolitan. June-Aug. - introduced 1896, as a novelty and called "dwarf golden yellow-flowering pea," "golden yellow sweet pea," etc. The flowers are much less fragrant than the true sweet pea.
Linn. Annual, erect and nearly glabrous, the branches and flower-stalks 4-angled: leaves ovate, shortly petioled, blunt: flowers racemose, numerous, their variegated blue corollas making a magnificent show in early spring. Cosmopolitan in the tropics. B.M. 3034. B.R. 1137. P.M. 13:223.
aa. Leaves foliolate (compound). b. Flowers striped with brown or red. longirostrata, Hook. & Arn. Greenhouse plant, herbaceous or somewhat shrubby, much branched, 3 ft. high: branches long, slender, glabrous: petioles 1 1/2 in. long; leaflets 3, oblong, with a minute mucro, glabrous above, hoary beneath, with very short, appressed, silky hairs: racemes erect; calyx with 2 upper lobes ovate, the 3 lower ones lanceolate; flowers as many as 25 in a raceme, yellow with reddish or reddish brown stripe along the back of the unopened flowers; standard wider than long, reflexed, notched. W. Mex., Guatemala. B.M. 7306. F.R. 1:809. - Flowering from Dec. to March. Intro, into Kew through the U. S. Dept. Agric. in 1891.
bb. Flowers not striped, pure yellow.
Linn. A woody perennial, 2-4 ft., with stout round branches, the whole plant silky-hairy: leaflets 1 1/2-2 in. long, obtuse, cuneate below, membranous: flowers 12-20 in a raceme, yellow, at least 1/2in. long: pod nearly sessile, loosely hairy. Common throughout the tropics. B.R. 377.
Jacq. Stout, much-branched shrub, 4-5 ft. high: branches terete, appressedly silky; stipules when present petiolulate, obovate and leaf - like, obsolete or wanting on many petioles: leaflets broadly obovate, obtuse or mucronulate, glabrous or minutely pubescent on one or both sides: racemes terminal or opposite the leaves, loose, many-fid., the flowers usually more than 1 in. long; calyx and pod pubescent; wings transversely wrinkled and pitted. S. Afr -Cult, in S. Fla.
C. Tropeae, Mattei. An erect or prostrate annual: racemes lateral, often 20-flowered or more; flowers small, yellowish. Italian Somaliland.