Many gardeners in cold-winter climates think of late winter and spring as the time to start seeds. They spend the fall reaping the joys of the year’s growing season and thinking of what they could do better next year. But fall is a great time to sow seeds to enrich the fall floral display and get an early start on next year’s garden.
There are a few main types of flowers that do especially well with a fall sowing:
- Cool-loving annuals
- Annuals that start growing early in spring
- Biennials
- Certain types of perennials
Cool-Loving Annuals
Many gardeners find that, by this time of year, some of the plants in their flower garden have started to look straggly or have died. A great solution for those empty spaces is to do a new sowing of annual flowers that love cool weather. Annuals that love cool weather and grow quickly from seed include sweet alyssum, candytuft, calendula, and sweet pea.
Annuals For Early Spring
Some annual flowers sprout earlier and with a higher germination rate if their seeds are sown in the fall instead of in springtime. Examples of annuals that you can sow in fall include:
- Annual poppies
- Love-in-a-mist (Nigella spp.)
- Annual clary sage (Salvia viridis syn. Salvia horminium), also known as painted sage
- Scarlet sage (Salvia coccinea), also known as Texas sage and hummingbird sage, and its cultivar ‘Lady in Red’
- Calliopsis (Coreopsis tinctoria)
- Bells of Ireland (Moluccella laevis)
- California poppy
- Snapdragon
- Larkspur (Consolida spp.)
- Clarkia (Clarkia spp.)
- Mexican tulip poppy (Hunnemania fumariifolia)
- Blue woodruff (Asperula orientalis)
- Queen Anne’s thimbles (Gilia capitata)
- California bluebell (Phacelia campanularia), also known as desert bluebell
- Tall verbena (Verbena bonariensis), generally hardy in USDA zone 7 and hotter
Two relatively reliable guidelines to follow are whether the annual has a reputation for self-sowing from season to season and whether it is generally considered a “hardy annual” (often abbreviated on seed packets as “HA”). These seeds can be sown after frost as well as before frost. After fall frosts, you can also sow calendula.
Biennials
Biennials, plants that form leaves their first year and bloom their second year, are ideal candidates for late summer or early fall sowing. Biennials that can be sown in fall include:
- Foxglove (Digitalis spp.)
- Honesty (Lunaria annua), also known as silver dollar plant
- Evening primrose (Oenothera spp.)
- Canterbury bells (Campanula medium)
- Sweet William (Dianthus barbatus)
- Hollyhock (Alcea spp.)
- Black-eyed Susan (Rudbeckia hirta)
Certain Perennials
When sowing seed of perennial flowers, a good guideline is to look at how they propagate themselves in nature. Many perennials generally drop their seeds in late summer or early autumn, including:
- Purple coneflower (Echinacea purpurea)
- Blanket flower (Gaillardia spp.)
- Columbine
- Shasta daisy (Chrysanthemum x superbum)
- Feverfew (Tanacetum parthenium syn. Chrysanthemum parthenium)
- Some monkshood species (Aconitum spp.), also known as wolfsbane
- Some perennial sunflowers
- Many milkweed species (Asclepias spp.)
- Perennial rudbeckias (including Rudbeckia subtomentosa and Rudbeckia triloba)
- Some perennial salvia species
An easy way to add more plants to your garden is to follow nature’s guidelines by doing the same with seeds that you have bought or gotten from a friend.
Don’t be concerned if you don’t see seedlings this fall. Some perennials form seedlings before winter, but others have seeds that need a period of cold before germinating and will wait till spring before they sprout. If you do see seedlings this fall, mulching them over the winter is a way to help ensure their survival. Wait until the ground freezes before you mulch them.
Fall Sowing: High Value for Little Effort
Fall sowing is an inexpensive, low-effort way to add fall color to your flower garden and start preparing it for next year’s growing season. Experiment with what annuals bloom well from a fall sowing in your area and what plants grow best the following season from a fall sowing.
For information on a related subject, see Fall Sowing of Seeds in the Vegetable Garden.
