Growing guide

How to grow zinnia

Cheerful and fun, zinnias are half-hardy annuals grown as a bedding display or cut flower crop for a sheltered and warm site. They perform best in a good summer.

Quick facts

  • Half-hardy annuals that last for one season
  • Zinnias are best grown on sheltered, warm, free-draining sites
  • Can grow as a cut flower crop, as blocks of bedding or in containers
  • Flowers in summer through early autumn, peaking in August and September
  • Their height depends on cultivar and on growing conditions. The average range is 30-90cm (1-3ft)
  • Long-lasting flowers
  • Raise from seed in late April-early May or buy as seedlings
  • Plant out when danger of frost is passed in late May/early June
  • Dead head or cut blooms to promote flowering

All you need to know

Before you get started
Ongoing care
Pruning and training
While we think all this information will be helpful to you, we always recommend to read the instruction labels on your plants.

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