Helianthemum
(from helios, the sun, and anthemon, a flower). Sun Rose. Including Fumana. ORD. Cistineae. A genus of showy, hardy, annual or perennial herb or sub-shrubs, often prostrate. Nearly 150 forms have been described as species; but, according to Bentham and Hooker, only about thirty are entitled to specific rank. They are natives of North, Central, and South America, and the Mediterranean region; a few extend to other parts of Europe and Western Asia, four species being members of the British Flora. Racemes secund, sometimes corymbose, sometimes paniculate; and before the flowers expand, the racemes at the top are bent or twisted backwards, becoming gradually erect as the flowers open. Leaves opposite and alternate. All the species are of easy culture in a sandy-loam soil, and are best adapted for banks and rockwork. The annual species must be raised from seed. The perennials may be similarly increased; but it is better to trust to cuttings, which root readily in a sandy soil, if kept shaded until established. The following is a selection of the more important species and varieties.
H. atriplicifolium (Atriplex-leaved). fl., petals yellow, large; peduncles racemose, hairy. June. l. stalked, broad-ovate, bluntish, waved at the base, tomentose on both surfaces. Branches white from tomentum. h. 4ft. Spain, 1659. Shrub.
H. canadense (Canadian). fl. pale yellow, minute, crowded; peduncles very short, one to three-flowered. Summer. l. oblong-linear; margins usually revolute; under surface tomentose. Branches very erect, pubescent. h. 1ft. North America, 1823. Herbaceous. (S. C. 21.)
H. carolinianum (Carolina). fl. yellow, 1in. across. May and June. l. shortly stalked, lanceolate, denticulate, hairy. Base shrubby. h. 6in. to 12in. South United States. (S. C. 99.)
H. formosum (showy).* fl., petals yellow, marked with a black spot at the base of each, large; peduncles villous. Summer. l. shortly stalked, obovate-lanceolate, tomentosely-villous; younger ones hoary. Branches canescent. h. 4ft. Portugal, 1780. Shrub. (B. M. 264; Gn. xxvi., 420, under name of Cistus formosus.) H. Fumana (smoky). fl. bright yellow. June. l. linear, fleshy, thinly hairy. South-western Europe. An elegant sub-shrub, of Heath-like habit. (S. C. 16.)
H. globulariaefolium (Globularia-leaved). fl. citron-yellow, black-spotted, in dense racemes. Summer. l., radical ones long-stalked, ovate-oblong, hairy, upper surface furrowed; cauline ones sessile, lanceolate. Stems ascending, almost simple, herbaceous. h. 9in. Spain and Portugal, 1752. (B. M. 4873, under name of H. Tuberaria.)
H. guttatum (spotted). fl. yellow, with red spot at the base of each petal, in unilateral cymes. Summer. l. opposite, sessile, oblong-linear, hairy. h. 6in. Europe (Britain), North Africa, and West Asia. Annual.
H. halimifolium (Halimus-leaved).* fl. bright yellow, large, slightly spotted at the base of each petal. Summer. l. ovate-lanceolate, acute, wavy, pubescent. h. 3ft. to 4ft. Spain. Shrub. (S. C. 4.)
H. italicum(Italian). fl. yellow, small; racemes simple, hispid. Summer. l., lower ones stalked, ovate; upper ones linear-oblong, almost sessile. Branches procumbent, long, hispid, shrubby. h. 3in. Europe, 1817.
H. laevipes (smooth-stalked). fl. yellow. Summer. l. linear, needle-like. h. 1ft. South-western Europe. A beautiful little shrub, requiring shelter during severe weather. (B. M. 1782, under name of Cistus laevipes.)
H. lavandulaefolium (Lavender-leaved). fl. yellow; racemes crowded. Summer. l. oblong-linear, with revolute margins; under surface tomentose, hoary. Stem shrubby, erect, branched; branches long, terete, canescent. h. 1ft. Mediterranean region, 1817.
H. ocymoides (Ocymum-like). fl., petals yellow, with a dark base, crenated; peduncles somewhat panicled, pilose. Summer. l. sessile, ovate-lanceolate, obtuse. Stem branched; branches, leaves, peduncles, and sepals beset with long loose hairs. h. 1ft. to 3ft. South-western Europe, 1800. Sub-shrub. (B. M. 5621.) H. algarvense (S. C. 40), H. candidum (S. C. 25), H. rugosum (S. C. 65), represent forms of this variable species.
H. polifolium (Polium-leaved). fl. white, marked yellow at the base; petals crenulated; racemes terminal, secund. Summer. l. oblong-linear, with revolute margins, tomentose on both surfaces. Stem shrubby, branched; branches procumbent, densely tomentose. Europe (Britain), North Africa. SYN. H. pulverulentum. (S. C. 88.) H. roscum is a beautiful variety, with rosy-red flowers. (S. C. 55.)
H. pulverulentum (powdery). A synonym of H. polifolium.
H. scoparium (broom). fl. yellow, small, by twos or threes at ends of branches, on naked pedicels; sepals five, three of which are oval and pointed, and two subulate; corolla twice as long as calyx. May and June. l. alternate, linear, without stipules. h. 3in. California, 1848. Perennial.
H. serpyllifolium (Thyme-leaved). A synonym of H. vulgare ovalifolium.
H. umbellatum (umbellate). fl. pure white, in a whorled raceme, ending in an umbel. June. l. linear-oblong, with revolute margins, ciliate, viscid when young. h. 9in. to 18in. Perennial. (S. C. 5.)
H. vineale (vineyard). fl. yellow; racemes simple. Summer. l. variable, obovate, ovate, or elliptical, pilose. Stem suffruticose, procumbent, branched, ascending, tomentose, evergreen. Europe, 1772. H. vulgare (common).* fl. yellow; racemes loose; pedicels pilose. Spring and summer. l. scarcely revolute at the margins; under surface hoary; upper surface green, pilose. Stem shrubby, procumbent. Branches elongated. Europe (Britain), North Africa, and West Asia. (Sy. En. B. 168.) A curious variety, or (according to Bentham) an accidental deformity, occasionally seen in gardens, and supposed to have been originally found near Croydon, with small, narrow, deeply cut petals, has been figured under the name of H. surrejanum. The Rock-roses of our gardens are chiefly varieties of this species, which, under cultivation, varies much in the colour of its flowers. The following are amongst the most distinct of the innumerable forms:
H. v. barbatum (bearded). l. ovate or elliptic-lanceolate, clothed with long white hairs. (S. C. 73.)
H. v. hyssopifolium (Hyssop-leaved). fl. coppery-red (S. C. 58) or saffron-coloured (S. C. 92). l. flat, linear-lanceolate or lanceolate; upper surface glossy. Of the one with coppery-red flowers, there is a double form.
H. v. macranthum (large-flowered). fl. whitish, yellow at the base; racemes terminal, secund, simple. Summer. l. flat, ovate-oblong, acutish, densely tomentose beneath, smooth above. Branches shrubby, procumbent, rather tomentose.
H. v. mutabile (changeable). fl. pale rose-colour, yellow at base, becoming almost white before petals fall. Summer. (S. C. 106.)
H. v. ovalifolium (oval-leaved). fl. yellow. l., lower ones roundish or oval, glossy green above, white beneath; margins more or less revolute. SYN. H. serpyllifolium. (S. C. 60.)