Fall Garden Planting: How to Time Crops Before Frost
A fall garden is planted in mid to late summer and timed backward from your first fall frost. Many cool-season crops taste better after a frost, and some, like garlic, are only planted in fall.
Count backward from your first fall frost
Spring planting counts forward from the last frost. Fall planting runs the other way: start from your typical first fall frost and work backward to find the last date you can plant and still harvest.
The basic calculation for any crop:
- Start with the crop's days to maturity from the seed packet.
- Add about two weeks as a "fall factor." Days get shorter and cooler as fall goes on, and plants grow more slowly than the packet's summer-based estimate.
- Add time to harvest. Many crops, like greens and roots, can be picked over several weeks.
- Count that many days back from your first frost date.
Cool-season crops that tolerate frost, such as kale, spinach, carrots, and cabbage, don't have to be finished by the first frost. A light frost often improves their flavor, and they can keep growing until a hard freeze. That buys extra weeks for crops that tolerate cold.
When to plant each fall crop
These windows are measured from the typical first fall frost and follow common university extension guidance. Broccoli, cauliflower, and cabbage are usually set out as transplants for fall; start their seeds indoors (or in a shaded spot outside) about four weeks before the transplant date.
| Crop | When to plant | Days to maturity |
|---|---|---|
| Carrots | Sow 10–12 weeks before first frost | 60–80 days |
| Kale | Sow 8–10 weeks before first frost | 50–65 days |
| Cauliflower | Transplant 9–10 weeks before first frost | 55–85 days |
| Cabbage | Transplant 8–10 weeks before first frost | 60–100 days |
| Beets | Sow 8–10 weeks before first frost | 50–65 days |
| Turnips | Sow 8–10 weeks before first frost | 40–60 days |
| Broccoli | Transplant 8–9 weeks before first frost | 55–80 days |
| Lettuce | Sow 6–8 weeks before first frost | 45–60 days |
| Spinach | Sow 6–8 weeks before first frost | 40–50 days |
| Cilantro | Sow 6–8 weeks before first frost | 45–70 days |
| Arugula | Sow 5–6 weeks before first frost | 30–40 days |
| Radishes | Sow 4–6 weeks before first frost | 22–30 days |
| Garlic | Plant cloves 2–4 weeks before first frost | 240–270 days |
In Chicago, where the typical first fall frost is November 5, that works out to: carrots Aug 13 – Aug 27; kale Aug 27 – Sep 10; lettuce Sep 10 – Sep 24; garlic Oct 8 – Oct 22. See every crop for Chicago.
Best crops for fall
- Leafy greens: lettuce, spinach, arugula, kale, and Swiss chard. Spinach and kale can carry on into early winter with a little protection.
- Root crops: carrots, beets, radishes, and turnips. Carrots left in the ground through a few frosts turn noticeably sweeter.
- Brassicas: broccoli, cauliflower, cabbage, and Brussels sprouts. In many regions the fall crop does better than the spring one, because heads mature in cool weather instead of bolting in summer heat.
- Garlic: planted in fall, harvested the next summer. Cloves go in a few weeks before the first frost so roots can establish before the ground freezes.
- Herbs: cilantro bolts quickly in summer heat but thrives in fall.
Getting fall crops started in summer heat
The catch with fall gardening is that you plant during the hottest part of summer. A few habits help:
- Keep seedbeds moist. Small seeds can dry out in a single hot afternoon. Water lightly every day until seedlings emerge, or lay a board or burlap over the row to hold moisture (remove it as soon as sprouts appear).
- Give some shade. Shade cloth or the shadow of taller crops protects young seedlings during heat waves.
- Sow a little deeper than in spring, where soil stays cooler and damper.
- Lettuce and spinach germinate poorly in hot soil. Sow them in the evening, or start them indoors and transplant.
Stretching the fall season
The first fall frost is often followed by weeks of mild weather. Row covers, low tunnels, and cold frames keep greens and roots producing well past it. A row cover over spinach or lettuce can add several weeks of harvest. See how to protect plants from frost.
Your city page lists the fall planting window for every crop that has one, based on your own first frost date. Look up your ZIP code.