CORVALLIS, Ore. — As fall approaches, consider letting some annuals go to seed. If winter isn’t too harsh, they may pop up next spring.
Annuals complete their life cycle in one growing season. Through summer, you can keep them blooming — and delay seed set — by deadheading spent flowers and fertilizing, said Brooke Edmunds, horticulturist with the Oregon State University Extension Service.
In September, relax your routine. Allow flower heads to dry and droop. Wind and birds will scatter ripe seed. You can also snip and collect seed into labeled paper bags to replant next spring or share with friends.
Good candidates for self-sowing
- Sweet peas
- Sunflowers
- Calendula
- Borage
- Nasturtiums
- Annual delphiniums
- Common garden poppies and Flanders poppies
- Clarkia
- Alyssum
- Petunias
Winter severity and site conditions will determine how reliably these return.
A note about hybrids
Annuals that are hybrid cultivars won’t come back “true to type” because they don’t produce uniform offspring. For most gardeners, that’s fine — instead of a pure stand of white alyssum, you may see splashes of purple.
Don’t forget herbs and greens
- Lettuce
- Dill
- Cilantro
These are willing self-sowers when seed heads are left to overwinter.
