Sweet williams

Sweet williams are a hardy biennial flower that can be sown during July

Sweet williams
Sow seeds in summer

Dianthus barbatus

Common Name
Sweet williams

Its pretty flowers come in pink, white, red and purple and it grows to around 45cm tall.

Growing Tips

Growing conditions

Grow in a sunny or part-shaded position in your flower border or in a large container.

When to grow

Sow seeds in July to flower in the following summer.

What you need

  • Gardening gloves
  • Packet of sweet william seeds
  • Trowel
  • Rake
  • Label and pencil

How to grow

  1. Sweet william seeds can be sown straight in to the ground where they are going to grow, so make sure the space you are going to sow is weed-free by using a trowel to remove the weeds.
  2. Rake the soil to a fine tilth and make some drills 5mm deep. The rows should be spaced about 30cm apart.
  3. If the soil is dry, water the soil before sowing and allow the drill to drain. Sprinkle the seed in thinly along the drill and cover up with soil. As they grow, if the plants are crowded, then thin them out to 15cm apart.
  4. In the autumn, transplant 30cm apart in to the flowering position.
  5. Keep the plants well watered during periods of dry weather and enjoy the beautiful flowers next summer.

Get involved

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