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Bright red Zinnia 'Scarlet Flame'

Flower seeds to sow in May

We pick five flower seeds that you can sow in May, including plenty of wildlife-friendly choices.

With spring fully underway, May is the month to sow seed directly, outdoors.


It doesn’t matter if you’ve already sown some of the seeds we’ve picked, below – by carrying out repeated sowings, you’ll be ensuring continued blooms well into autumn.

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Discover five flower seeds to sow in May, for summer and autumn colour.

With warmth in the air, you can sow zinnias outdoors in May for a splash of summer colour.


This airy annual not only looks good, but you can also use the anise-flavoured leaves for cooking. A brilliant plant for wildlife, it’s particularly popular with hoverflies. Direct sow dill now for summer blooms.

Delicate umbels of bright yellow dill flowers
Delicate umbels of bright yellow dill flowers


May is the final month to sow cornflowers (Centaurea cyanus), to ensure you get blooms the same year. They look particularly impressive when planted with other meadow plants, such as corn poppies.

A striking blue cornflower
A striking blue cornflower


Ever popular and for good reason, towering sunflowers are exciting annuals to grow. Try growing monster cultivars like ‘American Giant’, or shorter varieties such as ‘Moulin Rouge’ for cut flower arrangements.

Sunflower 'Shock-o-Lat', with a brown inner ring on the usually just-yellow petals
Sunflower ‘Shock-o-Lat’, with a brown inner ring on the usually just-yellow petals


In shades of purple, pink and blue, scabious flowers are a real magnet for butterflies. Some are hardy perennials, such as Scabiosa columbaria ‘Butterfly Blue’, while tender species like Scabiosa atropurpurea are usually grown as annuals.

Scabious 'Pink Mist' in flower
Scabious ‘Pink Mist’ in flower


With warmth in the air, you can sow zinnias outdoors in May for a splash of summer colour. Here are 10 stunning zinnias you could grow.

Bright red Zinnia 'Scarlet Flame'
Bright red Zinnian ‘Scarlet Flame’

Bishop’s flower

Bishop’s flower, Ammi majus, is pretty annual, growing to around 1m in height. Sown en masse, the flowerheads mesh to form graceful white clouds. Try growing with other summer flowers like salvias, cornflowers and echinaceas.

Pretty white umbels of Bishop's flower, amongst grasses
Pretty white umbels of Bishop’s flower, amongst grasses

Cut flowers to sow in May