How to Grow Sweet William

Sweet William belongs to the Dianthus family of plants and is a cousin of the carnation. I love them for their fragrance and wide variety of colours in the red and pink tones. It’s an old fashioned flower that isn’t grown nearly enough these days. Sweet William is a biennial flower which means it grows leaves in the first year and flowers and sets seed in the second year. Now that June is here the plants are in full flower. As I walked the garden I took photos of the plants as a reminder to collect seed when the flowers have faded. I let the flowers fade but watch carefully as I want to collect them before they drop to the ground.

I love both the single and bicolour flowers these plants have. Each one has undertones of different colours near the center of the flower. I would love to grow some pure white flowers but haven’t seen seed for them, have you? Sweet William loves a well drained soil and full sun but I find that it doesn’t mind some protection from the hot afternoon sun. It bridges the gap between the spring bulbs and the roses so it’s nice to have in the garden.

Sweet William is best started from seed in late summer and transplanted to the garden before winter arrives. You want the plants to establish roots before cold weather arrives. I start my seeds inside and pot seedlings up to 4″ pots when they get their second set of leaves. Plants will grow to about 2′ high and should be spaced 8″-12″ apart. This is one tough plant. I added some to a container last fall and they survived our extremely cold winter. Now when I say cold, I mean cold for the west coast of BC. It dropped to -13C last winter and many plants were lost or damaged.

This flower makes a beautiful addition to bouquets so cut them frequently to encourage more flowers to grow. It’s also an edible flower and may have medicinal properties. Butterflies, bees and birds are attracted to Sweet William making it a good choice for the garden. There is nothing better than being able to grow flowers that attract beneficial insects to the garden.

Interested in growing biennial flowers? Here is a list of flowers to start this summer.

Digitalis or foxglove




Canterbury Bells


Sweet Rocket

Columbine or Aquilegia

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