How to grow annual flowers from seed
Annual flowers are easy to grow from seed. We show you how.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| At its best | yes | yes | yes | |||||||||
| To do | yes |
It's easy to succeed with annual flowers. Follow your seed packet's instructions but use your own judgement, too. Sowing temperatures vary between varieties; it's roughly 18-24 degrees celsius for half-hardy annuals and 8-16 degrees celsius for hardy annuals. Use clean pots or trays, and start a new bag of multi-purpose compost. Hardy annuals often resent root disturbance so if you sow these indoors, sow them in cells that can then be transplanted without disturbing the rootball.
You Will Need
- Seeds
- Seed tray or small pots
- Multi-purpose, peat-free compost
- Pea sticks
- Secateurs
Step 1
When seedlings have their first true leaves, carefully prick them out into small individual pots or seed trays. Grow on in warmth for a few days, then move to a cooler windowsill.
Step 2
Direct sun is essential. Warmth-loving/delicate kinds are best on a patio; traditional hardy annuals thrive in the open garden. In a poor summer or cold location, salpiglossis, eustoma or large-flowered zinnias do best under glass or in a polytunnel.
Step 3
Annuals need fertile soil enriched with a little well-rotted compost and general fertiliser, such as blood, fish and bone. Use a multi-purpose compost for containers, and apply liquid tomato feed weekly from June onwards.
Step 4
Cut flowers need straight stems, so support is essential for taller species. Use pea sticks to provide support and tie plants to them where necessary.
Step 5
Unless you cut all annual flowers as they grow, you must remove spent blooms to prevent plants setting seed - otherwise they'll stop flowering. Snip off fading flower-heads regularly to promote a fresh flush of buds.
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