Simple Guide to Sowing Different Types of Seed (Pictures)

Germination is triggered by the correct combination of light levels, temperature and moisture – get these right, and the seed will start to grow.

Related content:
Nine tips for seed-sowing success

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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).

Polyanthus

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

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.