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.
(Latin, convolvo, to entwine). Con-volvulaceae. Includes Calystcgia. Bindweed. Annual and perennial herbs, grown mostly in the open; some are twiners.
Sometimes suffrutescent, twining, trailing, erect or ascending, with filiform, creeping rootstocks: leaves petiolate, entire, toothed or lobed, generally cordate or sagittate: flowers axillary, solitary or loosely cymose, mostly opening only in early morning; corolla cam-panulate or funnelform, the limb plaited, 5-angled, 5-lobed or entire. - A genus of about 175 species, widely distributed in temperate and tropical regions. Convolvulus and Calystegia are no longer kept separate. As Convolvulus Sepium is the type of both genera, they are therefore synonymous. When the flowers of C. occidentalis are borne singly, the calyx bracts are broad and Calystegia-like; when borne in clusters the bracts are greatly reduced.
The species thrive in a variety of soils without especial care. The greenhouse species do best in a soil with considerable fiber. The hardy perennials are usually propagated by dividing the roots, otherwise by cuttings or seeds, the tender species preferably by cuttings. C. tricolor is the most important of the hardy annuals. It may also be started in the greenhouse, and makes an excellent plant for the hanging-basket. All are vigorous growers, and may become troublesome weeds in some places if not kept within bounds. C japoni-cus and C. Sepium should be used with caution. This is the chief reason why the hardy perennials are not often found in well-kept gardens, except along wire fences or lattice screens, where the turf is laid up close so as to allow only a narrow border for the roots. The double-flowered form of C. japonicus is seen to best advantage in half-wild places, or on rocky banks, where shrubs make but a stunted growth. Here it will grow luxuriantly, forming graceful festoons from branch to branch, and covering the ground with a pretty mantle of green. (J. B. Keller.)
C. purpureus, the common morning-glory, and many related species are to be found under Ipomoea.
A. Calyx with 2 membranaceous bracts at the base: peduncles usually 1-flowered (Calystegia.)
B. stem prostrate, 8 in. to 2 ft. high: peduncle usually shorter than the Ivs.
(C. villosus, Gray. Calystegia villosa, Kellogg). Plant densely white-villose throughout: stem prostrate, scarcely twining: leaves slenderpetioled, reniform-hast ate to sagittate, the upper acuminate, 1 in. or less long, the basal lobes often coarsely toothed: bracts oval or ovate, completely inclosing the calyx: flowers cream-yellow, 1 in. long. C alif. - Perennial.
Similar to the preceding but foliage velvetyor plushy pubescent. Calif. - Perennial. Other closely related Californian species are C. saxlcola, Eastw., C. deltoldeus, Greene, C. Berryi, Eastw. and C. atriplicifolius, House.
bb. stem twining or trailing, 3-10 ft. high: peduncle exceeding the leaves
(Calystegia pubescens, Lindl.). California Rose. Fig. 1047. Hardy perennial herbaceous twiner: growth very vigorous, often 20 ft.: whole plant more or less densely and minutely pubescent: leaves hastate, lanceolate, obtuse or broadly acute, with angular or rounded lobes at the base, variable, occasionally without lobes, rarely sharp lanceolate: flowers bright pink, 1-2 in. broad, produced freely during the summer months and remaining expanded for several days. Japan and E. Asia. The double form is now naturalized from S. E. N. Y. to D. C. and Mo. P.M. 13:243. F.S. 2:172. B.R. 32:42. - The double form is completely sterile, with narrow wavy petals, irregularly arranged, the outer somewhat lacerate. A valuable decorative plant for covering stumps and walls. In rich soil the roots spread rapidly, and will smother out all other plants unless confined in tubs. The Calystegia pubescens of Lindley has been wrongly referred to Ipomoea hederacea, but the two plants are very different, the former being perennial and the latter annual.
See Journ. Hort. Soc. 1:70 (1846). The plant is commonly confounded with C. Sepium.
Fig. 1047. Convolvulus japonicus. (X 3/8)
Hardy perennial, herbaceous or with suffrutescent base: stem twining, several feet high, glabrous or minutely pubescent: leaves from angu-late-cordate, with a deep and narrow sinus, to lanceolate-hastate, the posterior lobes often 1-2-toothed: peduncle 1-flowered or proliferously 2-3-flowered, bracts ovate or lanceolate, usually completely inclosing the calyx, variable; corolla white or pinkish, 1-2 in. long; stigmas linear. Dry hills, Calif. - Listed as early as 1881.
An admirable plant for rockeries. Several related species are native also to Calif.: C. cyclostegius, House, C. Bing-hamise, Greene, C. polymorphus, Greene, C. Greenei, House, C. dridus, Greene, C. purpuralus, Greene, C. illecebrosus, House, C. gracilentus, Greene, and C. Iongi-pes, Wats.
(Calystegia Sepium, R. Br.). Rutland Beauty. Fig. 1048. Perennial trailer, 3-10 ft. long, glabrous or minutely pubescent: leaves round-cordate to deltoid-hastate, the basal lobes divaricate, entire or angulate: flowers white, rose or pink, with white stripes. F.S. 8:826. B.M. 732. A.G. 12:638. Gn. 50:514. - A very variable species. Cosmopolitan in temperate regions. An insidious weed in moist soil. The native forms have been called C. interior, House, Rocky Mt. region; and C. americanus, Greene, in the eastern states, but are difficult to distinguish. variety repens, Gray (C. repens, Linn.). Pubescent: stems. trailing or sprawling: the basal lobes of the leaves obtuse or rounded. Coastal region from Que. to Fla.
Fig. 1048. Convolvulus Sepium. (X 1/4)
aa. Calyx without bracts: peduncle 1-6-flowered (Eucon-volvulus.)
B. stem prostrate, trailing, glabrous or minutely pubescent.
Strong perennial roots: stem herbaceous, slender, prostrate, rarely branched, minutely villose: leaves alternate, round-ovate, obtuse, short-petioled: flowers blue to violet-purple, with a lighter throat, 1-2 in. across, very handsome. Africa B.M. 5243. F.S. 21:2183. Gn. 39:52. - A free bloomer through the summer. On dry banks each plant forms a dense tuft which throws up many graceful shoots. Not hardy north of Philadelphia.
Hardy perennial trailer, deciduous: stem angular, glabrous: leaves cordate-sagittate, gray-green, the lobes entire or dentate: sepals glabrous, ovate, obtuse; corolla white, creamy or light pink. Asia Minor. - The large tap-roots supply the resinous cathartic drug scammony.
bb. stem erect or ascending, silky.
stem shrubby, half-hardy, 1-4 ft. high: leaves persistent, lanceolate or spatulate, silky gray: infloresence a loose panicle, 1-6-flowered; flowers white or tinged with pink, borne freely during the summer. S. Eu. - Valuable as a pot-plant for greenhouse or window decoration, or trained to a warm wall. Confused with
Tender perennial: leaves linear-lanceolate, acute, slightly villose: flowers bright pink, borne freely in loose, umbellate panicles in the summer. Greece. B.M. 289 (as C. linearis). - Many plants now passing as C. oleaefolius are C. Cneorum. The latter may be distinguished by its broader, blunter, silvery-villose leaves, lighter-colored blossoms and taller growth.
(C. minor, Hort.). Fig. 1049. Hardy annual: stem trailing, ascending 6-12 in., angulate, densely covered with long brownish hairs: leaves linear-oblong or subspatulate, obtuse or rounded at the apex, usually pubescent but sometimes glabrous, the margin ciliate towards the base: peduncle 3-flowered, exceeding the leaves; sepals ovate, lanceolate, vil-lose, acute; limb of the corolla azure-blue, throat yellow, margined with white. S. Eu. B.M. 27. - One of the best annuals for the home border. Each plant covers a ground space of 2 ft., and blooms continuously throughout the summer. Flowers remain open all day during pleasant weather. There are many variously striped and spotted forms of this popular annual, none of which surpasses the type in beauty. A variety with pure white flowers is attractive. Other well-marked horticultural forms are :variety vittatus, prettily striped with blue and white. F.S. 3:298. R.H. 1848:121. varietycom-pactus, dwarf, and valuable for pot culture. Gt. 47, p. 635. A 5-petaled form is also recorded.
F.S. 8, p. 116, desc.
Fig. 1049. Convolvulus tricolor. (X 4/5)
A tender perennial, but may be treated as an annual, since it flowers the first season from seed: stem trailing or twining, 4-5 ft. long: flowers golden. - Valuable as a greenhouse climber and for hanging-baskets. Not sufficiently described for identification.
C. althaeoides, Linn. (C. italicus, Roem. & Schult.). stem prostrate, twining or climbing, if it finds support: upper leaves pedatifid.; lower ovate-cordate, crenate, silvery: flowers pink. May-Aug. Medit. region. B.M. 359. F.S. 10:1021 (as variety argyreus). R.H. 1864: 111. - C. ambigens, House, native from Mont, to New Mex. and S. Calif., is a close relative to C. arvensis. - C. arvensis, Linn. Slender perennial trailer, 1-3 ft. long, glabrous or nearly so: leaves ovate-sagittate or hastate, variable: flowers white or pink. Eu. and E. Asia. Naturalized in old fields through the Atlantic states and Calif. A troublesome weed in cult, grounds. - C. canariensis, Linn. Greenhouse evergreen: leaves oblong-cordate, acute, villose: flowers violet-purple; peduncle 1-6-flowered Canary Isls. B.M. 1228. - C. dahuricus, Herb. (Calys-tegia dahuricus, Fisch.). Hardy deciduous twiner, 3-6 ft.: leaves oblong-cordate, shortly acute: flowers pink or rose-violet. June, July. N. Eu. B.M. 2609. F.S. 10:1075. - C. erubiscens, Sims (C. acaulis, Choisy). Tender biennial: leaves oblong, hastate, the basal lobes toothed: flowers small, 5-lobed, rose-pink. Austral. B.M. 1067. - C. macrostegius, Greene. The plants in the trade under this name may be referred to C. occidentalis. - C. major, Hort., not Gilib.= Ipomoea purpurea. - C. ocellatus.
Hook. Stove evergreen: limb of corolla white, 5-angled; throat reddish purple: leaves sessile, linear, acute, 1-veined, villose. S. Africa B.M. 4065. - C. scoparius, Linn. - C. Soldanella, Linn. stems prostrate: leaves reniform: flowers pink or rose-colored. Sandy shores, Wash, to Calif.; also in Eu. and Asia.
S. W. Fletcher. H. D. HousE.†