All about growing Petunia from seed

Growing Guide

Sow petunia seeds indoors in February and March on the surface of a good seed compost and gently firm down. Lightly cover the seed with a fine sprinkling of vermiculite. Place the seed tray in a propagator or seal it inside a polythene bag, keeping the soil damp but not wet. Do not exclude light as this aids germination.

When seedlings are large enough to handle, transplant and grow them on in cooler conditions until large enough to plant outdoors. When petunia plants are well grown and all risk of frost has passed, acclimatise them to outdoor conditions over 7 to 10 days. Transplant into well drained soil at a distance of 30cm apart or grow in containers in full sun.

  • Key Information

    Height: to 30cm

    Spread: to 30cm

    Half-hardy annual

    Full sun

    Germination: 10 - 21 days

  • Sowing & Growing Schedule

    Sow Indoors: February to March

    Sow Outdoors: n/a

    Plant Out: May to June

    Blooms: July to September

  • Varieties we recommend

    Hula Hoop

    Prism Sunshine
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Top Tip

Petunias are some of the most outstanding bedding plants, thanks to their knack for creating a vibrant mass of colourful summer blooms. Petunias are versatile, ideal for different types of pot or hanging basket as well as in the ground. Petunias are divided into two main types: compact bushy petunias with an upright habit, and trailing petunias with stems up to 90cm long. Within both groups there's a huge choice of colours and flower shapes to choose from. Colours range from ultra-brilliant pinks, reds, and purples, to soft pastel shades and white. The size of the flowers ranges, too, and you can choose varieties with ruffled edges and bi-coloured blooms, along with single and double-flowered varieties.

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