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.
Annual and biennial, 3-6 ft.: stem erect, simple: leaves thin, serrate, somewhat pilose; root-leaves ovate-acute, subcordate, petiolate; stem - leaves ovate-lanceolate, acuminate at both ends: calyx-tube long, obconical, the teeth linear-acuminate, almost entire, spreading, shorter than the 5-fid, wheel-shaped corolla; flowers light blue, 1 in. broad, in long spikes, solitary or in 3's; corolla shallow, lobes pilose outside and at the apex; style long, strongly declined and upwardly curved: caps, cylindrical, grooved. Shaded low ground Canada to Iowa, south to Fla. and Ark. - Rarely cultivated It is possible that Phyteuma canescens is still cult. as C. americana.
bb. Flowers saucer-shaped or broadly bell-shaped, i. e., the tube shallower and the limbs more widely spreading than the bell-shaped.
c. stem - leaves linear-lanceolate, crenulate.
Fig. 765. Perennial, 2-3 ft.: stem erect: leaves glabrous, rigid, crenulate; root-leaves lanceolate-obovate; stem - leaves linear-lanceolate or spatulate, often 3 in. long: calyx-lobes acuminate, wide at the base, entire, half as long as the broadly bell-shaped corolla: flowers blue or white, pedicelled, solitary, terminal and axillary, often 1 1/2 in. long, 2 in. broad: caps, ovoid, 3-grooved. Eu. B.M.397. G.C. III. 43:384. Gn. 75, p. 30. G. 6:297. Gn. M. 14:9. G.W. 3, p. 292. C.L.A. 13:478; the white form in G. 13:71 and Gn. W. 23:Suppl. Jan. 27; the double white in G.C. 111.27:409 and G. 3:563. One of the best of all perennial campanulas. variety macrantha is a large-flowered form with flowers all along the stem Gt.44, p. 148. Gn. 48, p. 306. A.F. 6:383. S.H. 1:131. variety alba grandiflora and variety Backhousei are among the popular white-flowered forms. There are double and semi-double forms in blue and white. The double white is useful for cutting. For portraits of variety grandi-flora, see G. 27:458; 28:553, 673; G.W. 12, p. 433. variety coronata, Hort., is a semi-double white form. F.S. 7:699. The pictures in B.M. and F.S. show distinctly saucer-shaped flowers variety Moerheimei, Hort. White-fid., double, 2-3 in. diam.: excellent.
G.C. III. 27:414. G.M. 49:535. G.W. 6, p. 545; 12, p. 434. A.G. 23:497. variety marginata, Hort., has white flowers tinted blue on the borders. R.B. 32, p. 252. This species occasionally runs wild, especially in England. The leaves are very characteristic, and, once seen, are never forgotten.
Fig. 765. A narrow-flowered form of Campanula persicifolia.
cc. stem - leaves wider and coarsely toothed.
Perennial, 1-1 1/2 ft., glabrous: stem erect, simple, terete: stem - leaves 3-5 in. long, 4-6 lines wide, lanceolate, narrowed at both ends, crenate-serrate: calyx-lobes ovate-acute, broad, entire, erect, one-half shorter than the broadly bell-shaped corolla: flowers blue, often 2 in. wide, sessile, solitary or somewhat clustered, sometimes equaling the ovate-acute, dentate bracts. Mt. Olympus. P.M. 10:31. H.U. 3, p. 137. Gt. 7:202-Flowers like C. persicifolia. Quickly forms a dense carpet. Variable in color. variety alba, Hort. White flowers G. 19:440.
bbb. Flowers bell-shaped or tubular, not saucer-shaped. c. Infloresence a dense roundish head.
One of the most variable: perennial, 1-2 ft., typically pubescent: stem erect, simple, terete: leaves serrulate, lower ones rough with very short, stiff hairs, 1 1/2-3 in. long, 1-2 in. wide, with a cordate, ovate-oblong blade shorter than the petiole; upper ones sessile, ovate, acute: flowers violet-blue to white, in dense heads or glomes, 15-20 in the terminal heads, fewer in axillary ones. Eu., Armenia, Persia, Siberia; sometimes escaped in this country. Gn.M. 14:9. B.M. 2649 is variety speciosa, which has the largest flowers L.B.C. 6:505 is variety sparsiflora, with much smaller clusters. - This is one of the earliest flowering and easiest of cultivation Flowers typically dark purple, running into lighter varieties. variety dahurica, Hort., is probably the commonest form: terminal clusters 3 in. or more thick, a very characteristic infloresence The flower has a longer tube than
C. lactiflora and C. thyrsoides. G. 26:305. variety acaulis, Hort., is an almost stemless form with very large flowers: stems only 3-5 in. high. G.W. 9, p. 272. variety superba, Hort., is a cross of the dwarf variety with variety dahurica: large heads of deep violet flowers
cc. Infloresence a spike or raceme, dense or loose.
D. Color of flowers normally white or yellowish.
E. Corolla small, short-tubed.
Perennial, 2 1/2-6 ft.: stem erect, branching: leaves sessile, ovate-lanceolate, acutely serrate: calyx-lobes very broad, acute, serrulate, one-half shorter than the broadly bell-shaped corolla: flowers in a loose or dense panicle, which may be 3 1/2 in. long and thick; corolla white or pale blue, 1 in. long, nearly 1 1/2 in. broad: caps, ovoid, erect. Caucasus, Siberia. B.M. 1973. G.C. III. 50:438. Gn. 61, p. 29; 63, p. 90; 71, p. 418; 75, p. 89. G.M. 46: 168; 48:545. Gn. W. 23:623. The normally milk-white blue-tinged flowers are characteristic. variety coertilea, Hort., has light blue flowers - C. celtidifolia, Boiss., referred to the above, may be a strongly marked variety. C. biserrata, Koch, is also referred here.
Biennial, 1-1 1/2 ft.; stem grooved: leaves all covered with long hairs at the margin; root-leaves sessile, spatulate or obtusely lanceolate, 2 1/2 in. long, 3/4in. wide, in a dense rosette, lying on the ground; upper leaves more narrow and acute: flowers 40-50, sulfur or creamy yellow, in a dense thyrse-like spike, which may be 6 in. long and 2 1/2 in. broad; style exserted. Alps and Jura, 3,000-6,000 ft. B.M. 1290. L.B.C. 17:1644. - Intermingled with the flowers in the spike are leaves which are longer than the flowers, which is not true of C. lactiflora. Should not be confounded with C. thrysoidea, Lapeyr., which = C. speciosa, (see supplementary list). Apparently no blue or purple forms are known. The picture in B.M. shows a characteristic red-tipped calyx. Garden hybrids are reported with C. spicata (see Kew Bull. 1910, p. 322).
ee. Corolla large, long-tubed.