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How to Grow Zinnia Plants

Guide to Growing Zinnia, Profusion flower.

Zinnia plants are half hardy annuals. They range from 20 to 90 cm (8 to 36 inches) in height.

They bloom from summer through to the first frost.

When in bloom, they carry single or double blooms. The flowers are often pink, purple, red, orange, or white.

zinnia profusion flower
Profusion flower (above) and Common Zinnia (below).

Common Zinnia

They are able to grown in zones 2 through 10, and can be sown out in the garden following the last frost.

Common species of Zinnia grown in the garden include Profusion flower and 'youth and old age'.

Zinnia
Zinnia by Photofarmer.

Commonly Grown Zinnia Species Photographs and Plant Identification

Zinnia elegans

Zinnia elegans
Zinnia elegans (Elegant Zinnia / Common Zinnia / Youth-and-age), photograph by Forest and Kim Starr; CC.

Full growing Guide available at How to grow Zinnia elegans.

Zinnia angustifolia

Zinnia angustifolia
Zinnia angustifolia (Narrowleaf Zinnia), photograph by Eric Savage; CC.

Visit How to grow Zinnia angustifolia for an in-depth growing guide.

Zinnia grandiflora

Zinnia grandiflora
Zinnia grandiflora (Rocky Mountains Zinnia / Plains Zinnia), photograph by Patrick Alexander; CC.

Zinnia acerosa

Zinnia acerosa
Zinnia acerosa (Desert Zinnia / Wild Zinnia / Spinyleaf zinnia), photograph by Patrick Alexander; CC.

Zinnia haageana

Zinnia haageana
Zinnia haageana (Mexican Zinnia), picture by 阿橋 HQ; CC.

Commonly Grown Zinnia Hybrid

Zinnia Macarenia bicolor

Zinnia Macarenia bicolor
Zinnia bicolor Macarenia (Macarenia Zinnia), photograph by Swallowtail Garden Seeds; CC.

How to Grow Zinnia

Quick Zinnia Growing Guide and Facts

Common Names: Zinnia: Rocky Mountain; Common; Purple; Plains; Desert; Wild; Spinyleaf; Narrowleaf; Bush; Mexican.
Scientific Names: Zinnia elegans; Z. angustifolia; Z. grandiflora; Z. acerosa; Z. peruviana.
Life Cycle: Half hardy annual.
Height: 6 to 40 inches (15 to 100 cm).
Family: Asteraceae.
Native: Americas.

Growing Region: Zones 2 to 10.
Flowers: Summer until first frost.
Flower Details: White, yellow, yellow-green, cream, gold, burgundy, pink, red, purple, violet, orange. Multi, contrasting colours. Double ray florets; central disc. Dome. Papery.
Foliage: Green. Opposite. Linear through to Ovate.

Sow Outside: Cover seed. Following the last frost. Spacing 5 to 12 inches (12 to 30 cm).
Sow Inside: Germination time: one week to one month. Temperature 70 to 80°F (21 to 27°C). Seven or eight weeks in advance. Transplant outdoors following the last frost.

Care Requirements: Full sunlight or afternoon shade. Good drainage. Soil pH 6 to 7. Rich soil. Humus. Moist soil. Mix in manure. Regular watering to surrounding soil. Feed when transplanting. Feed at the start of flowering. Pinch tips.

How to Grow Zinnia

If growing Zinnia from seed, then sow outdoors following the last frost of spring. Lightly cover the seed once sown.

Plants should be spaced at 15 to 20 cm (6 to 8 inches; small), 25 to 30 cm (10 to 12 inches; medium), or 45 cm (18 inches; large Zinnia species) apart.

Ideally grow Zinnia plants in a sunny area of the garden that gets an afternoon shade. The plants are able to grow in most soils of pH 6 to 7. The soil should be enriched with manure for best results.

In cold areas, it may be a good idea to start off Zinnia seedlings indoors first. Do so about seven weeks in advance of transplanting.

It should take about one to three weeks to germinate Zinnia at a temperature of 20 to 27 degrees Celsius (68 to 80°F).

Transplant outdoors, just after the last possible frost of spring.

Purple Zinnia
Purple Zinnia by Dendroica Cerulea.

Caring for Zinnia

It is easy to look after Zinnia. Keep them well watered, and feed them in the spring.

Pinch back Zinnia plants to encourage branching. Feed again once they start to flower. Remove (deadhead) decayed flowers.

I hope that you enjoyed this guide on how to grow Zinnia plants. Learn how to grow Dahlia, Cyclamen, Chrysanthemum plant, and Helipterum plants in your garden.