Fall and winter harvests begin while summer is still in the garden. The right starting date depends on your average first frost, the crop’s days to maturity, germination time, whether you are sowing seed or setting out transplants, and how quickly growth slows as days become shorter.
Start with your local timing: enter your average first-frost date in the Seed Planting Calculator, then confirm the seed packet’s current directions for planting depth, germination temperature, and days to maturity.
Plan backward from the first frost
Use the first-frost date as a planning anchor, not a guarantee. Add the crop’s days to maturity and germination period, then allow extra time for slower autumn growth. Long-season crops usually need to be started first; quick roots and leafy greens can follow later.
Microclimates matter. A sheltered urban bed, an exposed rural garden, and a low spot where cold air settles can experience different temperatures on the same night. Keep notes from year to year and adjust the calculator’s result to match your garden.
Start long-season brassicas first
Broccoli, cabbage, cauliflower, Brussels sprouts, and kohlrabi often need the longest lead time. In hot-summer regions, starting them in containers can make temperature and moisture easier to manage before transplanting. Choose varieties whose listed maturity fits the remaining season, and do not assume every transplant will reach harvest before severe cold.
- Broccoli and cabbage: start early enough to establish sturdy transplants before the main cooling period.
- Cauliflower: protect young plants from severe heat and moisture stress because uneven growth can affect head development.
- Brussels sprouts: allow a particularly long season and choose a climate-appropriate planting window.
- Kohlrabi: compare days to maturity; many varieties mature sooner than heading brassicas.
Direct sow roots and hardy leafy crops
Carrots, beets, turnips, radishes, spinach, peas, chard, kale, lettuce, and other greens are commonly used in fall gardens, but they do not all share the same schedule.
- Carrots and beets: sow while enough growing time remains for usable roots. Keep the seed zone evenly moist during germination.
- Kale and chard: direct sow or transplant according to the variety and local season.
- Peas: allow more time than you might in spring because shortening days can slow growth.
- Lettuce and tender greens: use succession sowings rather than planting the entire seed supply at once.
- Radishes and baby turnips: reserve later windows for quick varieties, while still allowing for slower cool-weather growth.
- Spinach: wait for a suitable germination window if the soil is still hot, or start seed in a cooler protected location.
A practical starting sequence
| Approximate lead time before first frost | What to consider starting | Primary decision |
|---|---|---|
| 10–14 weeks or more | Brussels sprouts and longer-season broccoli, cabbage, or cauliflower | Check transplant age and days to maturity. |
| 8–10 weeks | Carrots, beets, kale, chard, kohlrabi, peas, and additional brassicas | Allow a buffer for slower autumn growth. |
| 6–8 weeks | Lettuce, Asian greens, mustard greens, cilantro, and quick root crops | Watch soil temperature and maintain moisture. |
| 4–6 weeks | Fast radishes, baby greens, and suitable turnips or spinach | Select quick varieties and protect from early cold when practical. |
These are planning ranges, not universal planting dates. Variety, climate, soil temperature, daylight, and the protection you can provide determine the final schedule.
Help seeds establish in late-summer heat
Warm soil can delay or reduce germination for cool-season crops. Sow at the packet’s recommended depth, keep the seed zone consistently moist without waterlogging it, and use temporary shade where appropriate. Containers can be moved to a cooler location while seed germinates, then returned gradually to stronger light.
A soil thermometer can help explain poor emergence. If one crop fails while others germinate, compare its preferred temperature range, planting depth, seed age, and moisture before reseeding.
Use protection without overheating the crop
Floating row cover and low tunnels can provide useful protection, but they require management. Secure fabric against wind, check temperatures on sunny days, and provide ventilation when a structure traps too much heat. Match the cover weight and support system to the crop and expected weather.
Row cover can also exclude insects when installed before pests reach the crop. Remove or manage it when pollination is needed, and inspect covered plants rather than assuming they are problem-free.
Build a fall garden instead of one planting date
Use two or three smaller sowings where the season allows. Succession planting spreads harvest and reduces the risk that one hot week, storm, or unexpected frost affects the entire crop. Label each sowing with the variety and date so you can refine next year’s schedule.
For the complete seasonal plan, read Growing a Fall Garden. You can also review the individual guides for carrots, cabbage, cauliflower, and spinach.
Choose seeds for the available window
Compare current packet directions and days to maturity in Vegetable Seeds. Choose crops that fit the time, temperature, and protection available in your garden rather than relying on a single nationwide calendar.