All about growing Sunflowers from seed

a bee taking nectar from a sunflower, zoomered in close

Growing Guide

Sunflowers come in a range of sizes and colours, with many now having multiple flower heads from a single stalk.

Sow indoors in March and April in individual 9cm pots. Sow 2 seeds per pot, 1cm deep in compost. Discard the weakest seedling after germination. Grow on until the risk of frost has passed, gradually aclimatising the plants before planting out.

Alternatively from April to June sow seeds thinly, 1cm deep in drills 30cm apart in well cultivated soil raked to a fine tilth. When large enough to handle, thin seedlings to 30cm apart.

  • Key Information

    Height: from 45cm to 300cm+

    Spread: to 30cm

    Hardy annual

    Full sun

    Germination: 10 - 21 days

  • Sowing & Growing Schedule

    Sow Indoors: March to April

    Sow Outdoors: April to June

    Plant Out: May to June

    Blooms: July to September

  • Varieties we recommend

    Ms Mars

    Firefox
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Top Tip

Sunflowers prefer a well drained soil in full sun. Tall varieties may need staking if sited in a particularly windy area.

For varieties offering multiple flowerheads deadhead regularly to encourage continuous flowering. If space allows once the flowers are spent at the end of the season leave the heads to form seeds which will provide food for wildlife through the winter.

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