Petalostemon
(from petalon, a petal, and stemon, a stamen; referring to the peculiar union of these organs in this genus). Prairie Clover. ORD. Leguminosae. A genus comprising about fourteen species of pretty, hardy or half-hardy herbs, usually perennial, gland-dotted, closely allied to Dalea; they are confined to the warmer parts of North America. Flowers rose-coloured, purplish-violet, or white; calyx teeth or lobes sub-equal; standard heart-shaped or oblong; heads or spikes terminal, or opposite the leaves, often pedunculate, sub-sessile. Leaves impari-pinnate; leaflets small, entire, exstipellate; stipules minute, setaceous. The best-known species in cultivation are P. candidus and P. violaceus; these thrive in a compost of sandy loam with a little peat or leaf mould. They may be increased by divisions, in spring. Both are hardy perennials.
P. candidus (white).* fl., corolla white; heads oblong, when old cylindrical. July. l., leaflets seven to nine, lanceolate or linear-oblong. h. 1ft. 1811. P. violaceus (violet).* fl., corolla rose-purple; heads globose-ovate, or oblong-cylindrical when old. July. l. leaflets five, narrow-linear. h. 1ft. 1811. (B. M. 1707.)