Guide to sowing seeds

Guide to sowing seeds

Find out when and where to sow different types of seed in this short guide.

Sowing seeds is something that some gardeners avoid, but it's easy when you know how. You just need to give seeds the right conditions, and they'll germinate.

Germination is triggered by the correct combination of light levels, temperature and moisture – get these right, and the seed will start to grow. Read our seed sowing tips for more advice.

We show you when and where to sow all kinds of seeds, indoors and outdoors, in this sowing guide.


Hardy annuals

Including: calendula, cornflower, nasturtium, poppy, sunflower, sweet pea.
Sow under glass: Feb-Mar (soil temp 8-12°C).
Sow outdoors: Mar-April (soil temp 6-12°C).

Hardy salads and veg

Including: beetroot, broad bean, chard, lettuce, pea, spring onion, radish, rocket.
Sow under glass: Feb-April (soil temp 10-18°C).
Sow outdoors: March-Sep (soil temp 8-18°C).

Half-hardy flowers

Including: cosmos, lobelia, morning glory, nicotiana, snapdragon.
Sow under glass: Mar (soil temp 16-24°C) – seeds must be sown indoors.

Tender perennials

Including: begonias, dahlia, fuchsia, heliotrope, pelargonium, salvia.
Sow under glass: Jan-Feb (soil temp 18-24°C) – must be sown under cover.

Frost-tender veg

Including: aubergine, chillies, courgette, French/runner bean, pepper, pumpkin, sweetcorn, tomato.
Sow under glass: April (soil temp 16-28°C).
Sow outdoors: May-June (soil temp at least 10°C).

Hardy perennials

Including: aquilegia, delphinium, echinacea, hellebore, lupin, rudbeckia, verbascum.
Sow under glass: Jan-Feb (soil temp 18-21°C).
Sow outdoors: April-June (soil temp at least 10°C).


Including: campanula, forget-me-not, foxglove, polyanthus, sweet william, wallflower, winter pansy.
Sow under glass: June (soil temp 12-18°C).
Sow outdoors: April-June (soil temp 10-18°C).

Trees and shrubs

Including: abutilon, acer, bonsai, cotoneaster, cytisus (broom), hawthorn, sorbus.
Sow under glass: Sep-Mar (soil temp 4-10°C).
Sow outdoors: Sep-Mar (soil temp 0-12°C).

Germination is triggered by the correct combination of light levels, temperature and moisture.


Using new compost

When sowing seeds, it's best to avoid using up old bags that have been lying around outdoors, even if unopened. For best results, start a new bag of compost and save old bags for mulching the garden.

Discover more ideas and inspiration

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