Sweet William Growing Guide

All you need to know to grow successfully!

Plant Family:
Plant Type:
Growing Difficulty:
Typical Zones Grown In:
4, 5, 6, 7, 8, 9

Planting Depth:

3-6 mm
Maturity Time:
2-3 Months
Companion Plants:
Lettuce, Radish

Planting Guidelines

The following are general guides to follow. However, nothing is set in stone. Feel free to experiment!

How to Start:
Direct Sow or Start Indoors if you want an extra challenge
When to Direct Sow:
March, April, May, June, July, August, September, October
Sprouting Time:
2-4 Weeks
Spacing (cm):
20 cm
Row Spacing (cm):
6-8 inches

Square Foot Spacing:

16 Plants
Sun Exposure:
Part Shade
Typical Season:
When To Harvest:
April, May, June, July, August, September
How to Harvest:
Cut Flower Heads

Tips to Growing Organically

Growing without the use of pesticides and herbicides is easier than you may think and it’s better for the environment!

Companion Plants:
Lettuce, Radish
Common Pests:
Aphids, Slugs, Caterpillars
Common Disease:
Powdery Mildew, Downy Mildew, Root Rot
Bonus Grow Tips:
Plant in cooler weather, harvest flowers when they are fully open

Sweet William (Dianthus barbatus) is a biennial or short-lived perennial flowering plant that is native to the Mediterranean. It is a member of the carnation family and produces clusters of flowers in shades of pink, red, white, and purple, with a spicy fragrance. Sweet William is commonly grown as an ornamental plant in gardens and is often used in cut flower arrangements. It prefers cool climates and well-draining soil, and blooms in late spring to early summer.

How to Grow Sweet William Organically

  1. Choose a planting site: Sweet William prefers full sun to partial shade and well-draining soil. It can be grown in containers or in the ground.
  2. Prepare the soil: Sweet William prefers loose, fertile soil. Amend the soil with compost or other organic matter to improve fertility and drainage. Sweet William is tolerant of a wide range of soil pH levels.
  3. Plant the seeds or seedlings: Sow Sweet William seeds indoors 8-10 weeks before the last frost or directly in the garden bed after the last frost. Plant the seeds 1/8 inch deep and 6-8 inches apart, or plant seedlings at the same spacing. Cover the seeds with soil and water gently.
  4. Water the plants: Sweet William needs consistent moisture to grow well. Water the plants regularly, especially during dry periods.
  5. Fertilize the plants: Sweet William benefits from regular applications of balanced fertilizer, such as 10-10-10. Apply the fertilizer according to package instructions.
  6. Provide support: As Sweet William grows, it may require support to prevent it from falling over. You can provide support by staking the plants or using a trellis.
  7. Deadhead the flowers: Sweet William will bloom from late spring to early summer. To encourage more blooms, deadhead the spent flowers by cutting off the flower stem just above the next set of leaves.

By following these basic steps, you can grow your own Sweet William and enjoy their fragrant, colourful blooms. Sweet William is a low-maintenance plant that is well-suited for beginner gardeners.

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