Autumn is a great season for annuals, low-maintenance perennials and evergreen shrubs to shine. In fact, some of the most popular flowers, like colorful mums, roses, dahlias, purple pansies and yes, even bright yellow sunflowers, all bloom around September and October.
Although each plant's needs may vary and some will be more winter-hardy than others, in general about a month before the last fall frost is sufficient in giving the plant enough time to establish itself and take root.
Fall is a great time to plant perennial herbs, which come back year after year and thrive in either pots or planting beds. Plant herbs such as thyme, oregano, mint, and sage any time from summer to mid fall, and you'll be able to harvest now and up until a hard freeze.
Mid-August to mid-October is an ideal time of year to plant new trees, though, that time frame can be stretched into November and December. To be 100% sure, measure soil temperature early in the morning for a few, consecutive days. If your soil is consistently 50° F or higher, you're good to plant.
"Fall is an excellent time to plant almost any perennial, with the exception of many ornamental grasses, which are better planted in spring," says Erin Schanen, Troy-Bilt's gardening partner, a master gardener volunteer and creator of The Impatient Gardener blog and YouTube channel.
Gardening in the fall provides a longer period with more 'good' days, as compared to the often tumultuous spring season. Plus, if you plant in fall you'll end up ahead of the game and won't have to rush to get everything done after winter. In fact, a good strategy is to plant perennials when you plant your fall bulbs.
For starters, spring-blooming bulbs should be planted in fall. Trust us: You'll be glad you planned ahead when you see them pop up after a long, dark winter! Get them in the ground any time before the ground freezes, which is from October to mid-December, depending on where you live.
From early fall through most of November is one of the best times of year to plant spring-blooming bulbs, cool-season annuals and vegetables, as well as many trees, shrubs, and perennials.
Late summer or early fall is an excellent time to plant mums, one of the symbolic flowers of the season. Practically any time in September that strikes your fancy is a good bet, so long as it's at least six weeks before the year's first frost.
Asters. These beautiful fall-flowering perennials are a lovely companion planting to chrysanthemums, the other stars of the autumn garden. Give asters full sun, and water to get them established (but don't overdo it; they don't like soggy feet).
The date that your ground actually freezes varies from year to year, of course, and some areas won't have frozen ground at all. If you're unsure, mid-November is a safe planting deadline for nearly everyone. - Get everything in the ground before the ground freezes.
Tip. Mid- to late-August is often an excellent time to plant fall flowers, as long as the weather isn't still so hot that the plants will suffer heat stress.
Winter pansies are cold weather all-stars. These cheery winter blooming flowers can freeze solid and emerge from that state ready to grow and flower. Other bedding plant flowers that grow in winter include nemesia, snapdragon, sweet alyssum and flowering stock.
Crabgrass, petunias, and snapdragons are types of annual that will not survive cold temperatures and will need to be cared for to survive winter.
Mums are the fall flower! They're sturdy, don't mind a light frost, and come in a rainbow of colors. Technically, they're perennials. But they won't come back if you don't get them in the ground by mid to late summer because they need to get their root systems established before the ground freezes.
You can transplant perennials anytime until the ground freezes in the fall, or wait to transplant them in the spring. Fall is an excellent time to transplant herbaceous perennials because your plants will then have three seasons to establish a good root system before hot summer weather sets in next year.
Spring-blooming perennials, especially in the bare root form, are best planted early in the fall. Planting in the fall while the soil is still warm will give the roots enough time establish properly. This allows the plants to emerge from well established roots, with a stronger start, the following spring.