When Is It Too Late to Plant in Fall? Here's Exactly When to Stop Digging

Fall is premium planting time—but how late is too late? In most U.S. regions, the aim is to plant at least four, better six weeks before your ground freezes, which may be as late as the second half of November. Your average first frost date, soil temperature, and plant type all play a role in how long your planting window is.

Here’s how to know when you still have time to plant, and which plants or conditions cannot handle a fall planting.

How to Know When It's Too Late

There are two key dates to keep in mind: the first frost when temperatures dip below 32°F, and when your ground freezes. 

While there is never a guarantee, looking at data of previous years’ first frost dates helps you know when to expect this year’s first frost. You want to give your new plants time to set down roots. For more tender plants such as quick-maturing vegetables, you also want to ensure they’ll produce before frost. There are also annuals, such as pansies, that you can overwinter and enjoy their flowers in winter or spring.

Generally, aim to plant trees and shrubs at least six weeks before your ground freezes, which may not even happen in your climate. This window allows the plant to adjust and develop some roots before winter arrives. In many US regions, you can plant up until mid-November.

With more rain in the fall, most shrubs and herbaceous perennials will have an easier transition planted now than in spring or summer. If you have plants waiting in their nursery pots, plant them as soon as possible before winter sets in. Even if you are nearing your first frost, your plants will fare better with the insulation of the ground than in their thin-walled plastic pots.

In many areas, fall is also a great time for sowing overwintering seeds of half-hardy annuals like calendula and nigella that need a winter chilling period (stratification) to germinate. For typical annuals, it’s important to understand the growth preferences, cold tolerance, and time to maturity of each plant variety.

Late summer into early fall is a good time to plant cold-tolerant veggies like kale or collards, flowers like pansies or violas, as well as cover crops such as crimson clover or fava beans. Depending on your start date and the plant’s days to maturity, you may have time to get a round of fast-growing peas, radishes, or lettuce in before frost.

When to Delay Planting Until Spring

Some plants are less likely to thrive with fall planting. Evergreens, which hold their foliage all year, don’t get the same energy break that deciduous plants do. They need longer to establish, months rather than weeks.

Certain plants are more susceptible to winter damage, such as bigleaf hydrangea and bluebeard (Caryopteris). Plants that typically need significant clearing of dead stems in spring belong to this category.

It is also important not to push the limits of hardiness zones. If you are experimenting with plants within a zone or two of your recommended hardiness zone, you’ll want to transplant in spring to give them the entire growing season to develop resilient roots. 

If your garden is wet or has areas of poor drainage over the winter, fall is not the time to plant species that require excellent drainage, such as dahlias, coneflowers, and lavender.