Zinnia

Plant Characteristics

Habit		herbaceous
Lifespan:	⌛	perennial, annual
Origin:	✈	S USA to Argentina

Cultivation

Exposure:	☼	sun
Water:	◍	moderate
Features:	✓	flowers
Flower features:	❀	red, orange, yellow, multicolored, single, double

Scientific Names

Asteraceae >

Zinnia >

Read about Zinnia in the Standard Cyclopedia of Horticulture

Zinnia (Johann Gottfried Zinn, 1727-1759, professor of medicine at Gottingen). Syn. Crassina. Compositae. Youth-and-old-age. Popular flower-garden subjects for summer and autumn bloom, mostly annual or treated as such. Annual, perennial, and subshrubby plants, mostly Mexican but ranging from Texas and even Colo. to Chile, probably 16-20 species: lvs. opposite, mostly entire: heads terminal, of fls. which are peduncled or sessile: rays pistillate, fertile, disk yellow or purple, its fls. hermaphrodite, fertile; involucre ovate-cylindric or campanulate, the scales in 3 to many series, broad, obtuse or rounded, more or less colored: achenes laterally compressed, 2-toothed at the summit and frequently 1-awned from the inner angle, rarely 2-awned. See the botanical revision by Robinson & Greenman in Proc. Amer. Acad. Arts & Sci. 32: 14 (1897). Illustrated historical sketch in Gn. 48, pp. 464, 465. The familiar zinnias (Figs. 4048-4050) are hardy plants, growing a foot or more high and covered from July until the first hard frost with double flowers 2 inches or more across. Several well-marked colors are commonly seen in zinnias—white, sulfur, yellow, golden yellow, orange, scarlet-orange, scarlet, flesh-color, lilac, rose, magenta, crimson, violet, purple, and dark purple. There are also variegated forms, but the solid colors are most popular. The zinnia is rich in shades of purple and orange, but lacks the blue and pink of the China aster and is poor in reds compared with the dahlia. Three forms or classes of the common zinnia (Z. elegans) may be noted here: I. Tall zinnias are ordinarily 20 to 30 inches high. This size and the next smaller size are the favorites for general purposes. The tall kinds are available in twelve and more colors. A robust race, which attains 28 to 40 inches under perfect conditions, is sometimes known to the trade as Z. elegans robusta grandiflora plenissima. It is also known as the Giant or Mammoth strain. This strain was developed after many years by Herr C. Lorenz and was introduced in 1886. A maximum diameter of 6 inches is recorded for flowers of this strain. In G.C. II. 26:461 is shown a flower measuring 4 by 4 inches, with about eighteen series of rays, the latter being so numerous and crowded that the flower is less regular than the common type. A specimen zinnia plant 3 feet high is attained in the North only by starting the seed early and giving perfect culture. II. Medium-sized zinnias range from 12 to 20 inches in height. They are available in several colors. Here belong most of the forms known to trade catalogues as Z. pumila, Z. nana, and Z. compacta. III. Dwarf zinnias range from 3 to 12 inches in height and are of two subtypes, the pompons and the Tom Thumbs. The pompons, or "Lilliputians," are taller-growing and smaller-flowered, generally about 9 inches high, with a profusion of flowers about 2 inches across. The Tom Thumb type represents the largest possible flower on the smallest possible plant. Both types are available in several colors, not all of which are yet fixed in the seed. Second in importance to Z. elegans is Z. Haageana. The single form was introduced to cultivation about 1861 and the double about 1871. It is dwarfer than most zinnias, and has smaller flowers, with a color-range restricted to shades of orange. It is distinct and pretty but less showy than the common zinnias. The first race of hybrids between Z. Haageana and Z. elegans appeared in 1876 under the name of Z. Darwinii. This group is said to resemble Z. elegans in size and color of flowers and to recede from Z. elegans in habit, being more branched and forming a broader and thicker bush. Zinnias are of the easiest culture, thriving in any deep good soil, whether loamy or sandy. The seeds may be sown about May 1, or whenever the soil is in fit condition for hardy annuals. Such treatment will give flowers from the first of July until frost. The young plants should be thinned so as to stand 1 to 2 feet apart, depending on whether they are of medium- or tall- growing habit. By midsummer the foliage should obscure the ground. For the very best results the seed may be started indoors about April 1, and the seedlings transplanted once or twice before being placed outdoors in permanent quarters. Dwarf varieties should be set 14 to 16 inches apart: taller kinds 2 feet each way. Zinnias are essentially coarse plants, but if the tall kinds are massed heavily in the borders or at some distance they produce striking and very acceptable effects. Their colors are strong, and the stoutness of stems and foliage add to the composition. The above text is from the Standard Cyclopedia of Horticulture. It may be out of date, but still contains valuable and interesting information which can be incorporated into the remainder of the article. Click on "Collapse" in the header to hide this text.

Related to the daisy (Asteraceae), Zinnia is a genus of annuals, perennials, and small shrubs. Soft leaves are light green. Leaves vary by species from linear to a broad spatula shape. Flowers of wild species usually are like daisies, while new varieties are primarily doubles with mostly hidden or missing disc florets. Common colors found are yellow, pink, orange, and red to mahogany, but there are many more colors.

Cultivation

Those commonly grown in the garden are usually frost-tender annuals which should be planted in sun, away from drafts. Keep soil moist, making sure it is well drained. They can tolerate dry periods. Extending the flowering can be done by deadheading often. Often will reseed.

Propagation

Seed.

Pests and diseases

Powdery mildew, caterpillars (which some gardeners plant Zinnias to attract).

Species

About 20 species. Zinnia elegans, (syn. Z. violacea) is the most common.

Species include:

• Zinnia acerosa (syn. Z. pumila, Diplothrix acerosa) - desert zinnia
• Zinnia angustifolia - narrowleaf zinnia
• Zinnia anomala - shortray zinnia
• Zinnia bicolor
• Zinnia elegans (syn. Z. violacea)
• Zinnia grandiflora - Rocky Mountain zinnia
• Zinnia haageana
• Zinnia linearis
• Zinnia maritima - Palmer's Zinnia
  • Zinnia maritima var. maritima
  • Zinnia maritima var. palmeri - Palmer's zinnia
• Zinnia peruviana - Peruvian zinnia

Gallery

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  Zinnia acerosa

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  Zinnia grandiflora

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  Zinnia peruviana

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  Zinnia bicolor

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  Single zinnia flower

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  A bed of zinnias

References

• Standard Cyclopedia of Horticulture, by L. H. Bailey, MacMillan Co., 1963
• Flora: The Gardener's Bible, by Sean Hogan. Global Book Publishing, 2003. ISBN 0881925381

External links

• w:Zinnia. Some of the material on this page may be from Wikipedia, under the Creative Commons license.
• Zinnia QR Code (Size 50, 100, 200, 500)