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USDA Zones, Frost Dates & Calendar FoundationsSuccession Planting Calendar for Continuous Harvest
Succession planting spaces sowings and mixes maturity dates so you pick a little every week rather than everything at once. The plan rests on your frost dates and on how fast each crop grows.
Key points
- Pick sowing intervals from how long each crop holds at harvest quality.
- Mix maturity dates and repeat sowings to smooth supply.
- Anchor the first and last sowings to frost dates, not zone numbers.
- Follow harvested beds with crops from a different family.
What is succession planting?
Succession planting means sowing the same crop at intervals, planting different varieties with different maturity times, or following one crop with another in the same space. All three keep harvests coming over a longer period.
Extension and sustainable agriculture programs describe it as a scheduling task. You decide how much you want each week, then work backward to sowing dates.
A grower aiming for steady supply might first decide the weekly amount wanted, then divide a season total by the number of sowings. Keep sowings small and frequent for perishable crops, since a large sowing that matures all at once is the problem you are trying to avoid.
How do you set the interval between sowings?
The interval depends on how long a crop holds in the field at harvest quality. Fast, perishable crops such as lettuce, radish and bush beans need frequent small sowings, while long-keeping crops such as winter squash need one planting. Check your crop's harvest window in an extension source.
For example, if a salad crop stays at good quality for about a week after maturity, sowing every week or ten days keeps a steady supply. Adjust after you see how your own plantings behave.
- Fast, perishable crops: frequent small sowings
- Moderate crops: staggered every few weeks
- Long-keeping crops: a single main planting
How do you use varieties with different maturity dates?
Early, mid and late varieties of the same crop let you plant once and harvest across a span. This works well for sweet corn, tomatoes and potatoes where repeat sowing is awkward. Seed catalogs list days to maturity, and extension variety trials can show how they perform locally.
Mix this with calendar-based staggering. For example, plant an early and a late variety at the same time, then repeat the early one two weeks later to fill the gap.
Do not rely on a single catalog number. Days to maturity are measured under typical conditions, and a cool spell or a dry spell stretches them, so compare each variety's date with your harvest log.
How do frost dates frame the first and last sowing?
The first sowing of hardy crops is limited by soil workability and soil temperature in spring. The first sowing of tender crops waits until frost risk has passed. At the other end, the last sowing must leave enough days to mature before your first fall frost, plus a margin for slowing growth.
Hardiness zones do not give these dates. Use frost probability tables from the nearest weather station or from your extension service.
How do you manage heat and cold breaks in the schedule?
Many cool-season crops struggle in midsummer heat. You may skip sowings during the hottest weeks, then resume as temperatures drop. Heat-loving crops can fill the gap.
Do the opposite at the cold end: use covers to keep a late sowing going. Keep notes on the weeks when each crop failed to germinate or bolted early, then place those weeks on your calendar as gaps.
Heat also affects germination. Lettuce seed, for example, can go dormant in warm soil, so a midsummer sowing may need shade, a cooler spot or transplants started indoors.
How do you plan space and soil for the next crop?
Every harvested bed is an opportunity for a follow crop. Pair crops from different plant families in sequence so you do not repeat pests or diseases, and consider how heavy feeders affect the soil. Use a soil test and local nutrient recommendations rather than adding fertilizer on a guess.
Compost or cover crops fill short gaps. Note that nutrient management rules and manure restrictions vary by state, so check local requirements.
Keep the calendar flexible. If a crop fails or a bed opens early, shift the following sowing instead of holding to the original date, and write the change down so next year's plan reflects it.
What does a simple one-bed schedule look like?
Imagine a bed that begins with an early spring crop of radish or spinach, followed by a warm-season crop such as bush beans after frost danger, and ends with a fall crop of lettuce or kale sown in late summer. Three crops fill the bed from spring to fall, each timed to your own frost dates.
Write down sowing and harvest dates each season. Over time the table shows how long each crop really occupied the bed, which is the main number you need to improve the next season's plan. The season total on your sheet should match the amount you actually want to eat or sell.
Sources and further reading
Last reviewed: November 2026. Educational information, ranges only. Confirm timing with your county extension office.