Zinnia

Family Asteraceae. Description: Zinnia is an extraordinarily colorful plant, distinguished by a wide range of bright, juicy hues that adorn the garden in summer and especially in autumn alongside the riot of colors in the surrounding nature. Interestingly, in America the zinnia is as beloved and esteemed as the aster is here. This is due not only to tradition but also to the extraordinary beauty of this flower. In cultivation here the most common is the elegant zinnia.

Elegant zinnia is an annual, vigorously growing, robust plant of spreading or compact habit, with an erect sturdy stem covered with coarse pubescence, 30 to 100 cm tall, with a few strong lateral branches. Leaves are ovate-pointed, sessile, opposite, and like the stem are covered with coarse hairs. The inflorescence is a head (capitulum) 5 to 15 cm in diameter depending on the cultivar.

Inflorescences of zinnia vary in shape and can be single, semi-double, or double. Ligulate flowers of various shapes and colors are arranged in 1–3 rows in single-flowered types and in more rows in double-flowered types. Flower colors are white, yellow, pink, orange, red, and lilac. Blue shades are absent from the zinnia color range. Tubular flowers are yellow, more rarely colored like the ligulate ones, forming a lush convex center.

Zinnia is notable for the purity of its colors and their great variety. Flowers of zinnia present bright (white, yellow, orange, red, and burgundy) and pastel (pink, salmon, lilac, and coral) tones.

Less commonly grown is another species of zinnia — the narrow-leaved zinnia or Hage, with smaller flowers, more often yellow and single-flowered. It forms bushes 40–45 cm high and blooms in mid-summer.

Zinnia has a large number of cultivated forms and varieties. They are grouped into categories called cultivar groups, according to inflorescence shape, plant height, and flowering time.

The variety of colors and inflorescence shapes of zinnia, as well as the height and form of the bush, give the plant great possibilities in design. Bright zinnias make magnificent groups and borders; low varieties will decorate a balcony, flowerbed, or rock garden. Both large- and small-headed varieties are suitable for bouquets; in water the plants retain an attractive appearance for up to 2 weeks.

Zinnia cultivar groups:

Dahlia-flowered (georginioid) — double, not very dense heads, 10–15 cm in diameter; ligulate flowers are spoon-shaped with their tips bent downwards and arranged imbricately. Plants are vigorous, up to 90 cm tall. They bloom from July into autumn. California giant — plants and heads similar, but the ligulate flowers are flat, arranged imbricately and densely. Chrysanthemum-flowered — the ligulate flowers are rolled into tubes, arranged imbricately and densely.

Cactus-flowered — the ligulate flowers are rolled into tubes and bent in different directions. The form 'Fantasia' is well known. Groups Pumila, Lilliput, and others are also known.

Cultivation and care:

Zinnia is a light- and heat-loving plant that does not tolerate even light frosts. For abundant and prolonged flowering it requires soil rich in humus, mineral elements, and nutrients, well worked and drained, with a neutral reaction. It grows well in sunny places sheltered from the wind. It does not tolerate excess soil moisture or prolonged drought, under which the heads become smaller and the outer flowers wither. It responds well to the addition of organic and mineral fertilizers at planting and in feedings, which are carried out 2–3 times per season. To prolong flowering and preserve the plant's ornamental value, spent inflorescences should be removed.

Zinnia is propagated by seeds, which are sown in late March–early April in boxes. Large seeds germinate in 4–6 days. With sparse sowing of large seeds, it is possible to avoid pricking out. Transplanting to a permanent place is done in late May–early June, when the danger of late spring frosts has passed, since zinnias absolutely do not tolerate temperature drops. Spacing between plants at planting is 25–40 cm. Young seedlings can be pinched to accelerate bushiness. Seeds may also be sown directly into open ground in late May after the last May frosts; in that case flowering will start later. Zinnia seeds are collected when the inflorescences brown.

Diseases and pests of zinnia:

Zinnia is susceptible to root and stem base rot, fusarium wilt, dry rot of stems, leaves and tips, gray mold, powdery mildew, bacterial spotting, viral diseases, and nematodes. It is damaged by several species of aphids, the common earwig, the meadow bug, spider mites, leaf-mining flies, cutworms, and slugs.