Perhaps you welcome the end of the growing season in November and December. But it might be worth considering one last planting activity in late fall or early winter.
Dormant seeding is the act of adding winter-hardy seed to bare soil or an established planting after a few frosts. Dormant seeding mimics nature. We purposely place seeds on the ground when they can't germinate and grow.
The benefit: You can broadcast a planting and forget about it until spring. This technique can also save time and watering next year. Furthermore, many wildflower species need exposure to cold, wet weather. Others tolerate it. Either way, nature slowly breaks down the seed coat and works the seed into the soil.
If you recently read our article about overseeding a lawn in fall, it is easy to confuse that technique with dormant seeding. Lawns in Zone 7 and north are usually overseeded in late summer and early fall.
Dormant seeding, on the other hand, takes place after a few touches of frost have occurred. Most plants have gone to sleep, except a few very cold hardy species. Seeds of cool season grasses and flowering plants--particularly natives--can be broadcast onto prepared surfaces as well as existing lawns or meadows. As you'll see below, the techniques differ somewhat.
One of the benefits is that there’s usually no need to water a dormant seeding. Winter weather should take care of the moisture.
Dormant seeding on bare soil:
Broadcast seed evenly onto the bare soil and rake or roll it very lightly. Then cover with straw, but not too deeply. About 80 percent coverage will work. A full bale of straw can cover about 100 to 125 square feet.
Some people cover a dormant seeding with a landscape blanket, such as those made of coir or other landscape-quality biodegradable materials. You can also hydro-seed a dormant planting.
Dormant seeding into an established planting:
Prepare the area by mowing it as low as the mower will allow. For low-mow lawns, this is probably a little more than one inch. For established meadows, it may be higher. The purpose of mowing is to expose as much bare soil as possible. Rake away the cuttings.
Broadcast seed onto the area. You may wish to cover the area with some of the cuttings or with straw. Either way, place them lightly onto the newly seeded area.About 80 percent coverage is good. The light should be able to reach the soil.
One benefit of dormant seeding is that you can gather flower seeds locally during October and add them to the grass mix. By propagating native wildflowers, you ensure the spread of local plant families, called "local ecotypes." This has value for native birds and pollinators.
Note 1: Don't use hay unless it is the "cooked" variety. Garden centers offer a number of cooked hay and straw products.
Note 2: If you need to smother weeds, use sheets of plain cardboard beneath the straw for a period of time before dormant seeding.