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How to sow half-hardy annuals


Half-hardy annuals are quick to flower and provide a burst of colour in summer borders and pot displays. To give them as long a flowering season as possible, sow seed early so that plants have plenty of time to establish before planting out.

Once risk of frost has passed, plant your home-sown plants outside. Many varieties sown indoors by March or April will start to flower as early as June.

How to do it


Fill a tray with seed compost, then sow a tiny pinch of seeds in each cell. Cover with vermiculite, water and place the tray in a propagator in a warm spot.


Once seeds have sprouted, wait until two pairs of leaves form. Transplant each seedling into a 7cm pot filled with sieved multi-purpose compost.


Water well after transplanting and keep the pots in a warm, bright place. Avoid exposure to bright sunlight, which can scorch the young leaves.


When all risk of frost has passed, move the plants to a cold frame or patio, bringing them in at night. After a week you can plant them outside.

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Talkback: How to sow half-hardy annuals
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JOHN GREAVES 24/04/2014 at 21:25

I have 10 fuchsia plugs potted up on my living room window sill a couple of them look a bit leggy should I snip their tops off or leave them be ?

Dave Morgan 24/04/2014 at 22:20

You can pinch them out, it will encourage them to bush up. Move them outside during the day, bring them in at night. Frost is the main enemy, so leaving them out on occasions won't do them too much harm.

NGLittleSeedlings 25/04/2014 at 07:51

I'd always recommend pinching them back