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Vegetable Crop Calendars (A–C)Warm-Season Vegetable Calendar
Warm-season crops are the ones that sulk, stall or die in the cold. Their calendar starts after the last frost and ends when your first fall frost arrives, so both dates matter.
Key points
- Start from your last frost, then check crop-specific soil and night temperature thresholds.
- Use transplants for long-season crops and direct seed for root-sensitive ones.
- Stage plantings from least to most heat-demanding.
- Count back from first fall frost to confirm each crop fits.
Which vegetables are warm-season crops?
Tomatoes, peppers, eggplant, okra, sweet potatoes, squash, cucumbers, melons and beans are typical examples. They grow best in warm soil and warm air, and most are damaged or killed by frost. Many stall when nights are cool even if no frost occurs.
Because they differ, check each one. Okra and sweet potatoes want more heat than bush beans, and melons need a long warm season.
Seed packets and your extension office will tell you which type is which. If a crop is new to you, read its packet before you decide a planting date, since warm-season crops differ in heat need and in length of season.
How do you decide the first planting date?
Start with your average last spring frost from the National Weather Service or your county extension office. Then add the soil and night temperature checks. Oklahoma State Extension advises waiting for okra soil to reach at least 70 degrees, Minnesota Extension suggests transplanting peppers once nighttime lows stay above about 50 degrees, and Clemson points to soil above 60 degrees at four inches for squash and pumpkins.
Those figures differ by crop, which is the point. One frost date does not fit every warm-season vegetable, so build a short list of crops and their thresholds.
A thermometer reading taken at planting depth on several mornings in a row is more reliable than a single warm afternoon.
Should you start these crops indoors?
Long-season crops such as peppers, eggplant and tomatoes are usually started indoors and set out as transplants. Minnesota Extension suggests starting peppers about eight weeks before setting plants outdoors. Some crops, such as squash and okra, are often direct seeded because they dislike root disturbance, though Oklahoma State notes okra transplants are possible with about four weeks of greenhouse growth.
Work backward from your planned transplant date and check packets or local advice for the lead time for each crop.
A worked example: if you plan to set peppers out in late May and the packet and local advice point to about eight weeks indoors, you would sow in late March. Replace the dates with your own frost and forecast.
How do you stage plantings?
A sensible order is tomatoes and peppers after the last frost once nights are mild, then squash, beans and cucumbers as soil warms, and then okra, sweet potatoes and melons last when soil is fully warm. This keeps tender crops from sitting in cold ground.
Add second plantings of quick crops, such as bush beans and summer squash, a few weeks after the first so harvests continue.
A short written order of planting, taped inside a shed door, keeps the sequence straight when spring gets busy and every crop seems to want attention at once.
How do you protect against late cold?
Keep row cover, cloches or blankets on hand until nights are settled. Water the soil before a cold night, since moist soil holds heat better than dry soil. Remove covers in the morning so plants do not overheat.
Hardening off transplants over a week or more reduces shock. Plant in late afternoon or on a cloudy day.
Wind is an underrated risk for new transplants. A simple windbreak, even a row of stakes with fabric, protects tender plants while they establish.
How do you plan the end of the season?
Count backward from your first fall frost. For each crop, add its days to maturity to its planting date and see whether the result fits. If it does not, choose an earlier variety or skip that planting.
For example, if a variety needs about 100 days and your first frost usually arrives in mid October, you would want to plant by early July at the latest, and earlier is safer. This is an example only, so use your own numbers.
What problems should you plan for?
Pests and diseases such as squash bugs, vine borers, hornworms and leaf spots appear in many regions, and heat stress can cause blossom drop. Rotation, spacing and mulch help.
Contact your county extension office for identification and current options. Follow every label, observe pre-harvest intervals, mind your state's applicator licensing rules and protect pollinators by avoiding open blossoms.
Blossom drop in extreme heat is a weather response rather than a disease. Keep soil evenly moist and avoid heavy feeding, and follow your soil test and local rules on nutrients.
Sources and further reading
Last reviewed: November 2026. Educational information, ranges only. Confirm timing with your county extension office.