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First & last frost dates for your hardiness zone.
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Planting Calendar by Zone
Pick a crop and your USDA zone band to get its planting window, whether it is a cool or warm-season crop, and its days to maturity — one at-a-glance sowing reference instead of a dozen date calculators.
Planting Calendar by Zone
Chlorova · updated for 2026
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Click “Calculate” to see your results.
Windows are general guides for each zone band and assume average frost dates and typical garden microclimates; a warm wall, a frost hollow or an early snap can move any date by weeks, so confirm with your own first and last frost dates using the frost and seed-starting calculators. Days to maturity are field averages from seed catalogs and vary widely between varieties and seasons. Warm-season crops that bolt or freeze, and cool-season crops that run to seed in heat, are the reason the same crop carries very different windows across the three bands.
Figuring out when to sow usually means bouncing between a frost chart, a seed packet and a dozen single-purpose date tools. This calendar collapses that into one lookup: choose a crop and your zone band, and it returns that crop's planting window, whether it is a cool or warm-season vegetable, and its days to maturity. It is the at-a-glance sowing reference for the whole bed plan — the big-picture when-to-plant map that tells you which direction to go, while the dedicated frost and date calculators give you the exact calendar day when you need one.
Planning a Season in Two Clicks
- Choose the crop you want to plan from the dropdown.
- Select the zone band that matches where you garden.
- Read the specific planting window shown for that crop and zone band.
- Note the season type so you know its frost behavior.
- Check days to maturity to see if it fits your season length.
- Repeat down your crop list to draft a full planting plan.
- Move warm-season crops earlier or later on your actual frost dates.
- Confirm any borderline or late-season date with the frost-date calculator.
How the Calendar Is Organized
This tool is a two-key reference rather than an equation. The planting window comes from a matrix whose rows are crops and whose columns are the three zone bands, so the intersection of your crop and your climate returns the specific guidance, and the season type and days to maturity are read from per-crop lookup tables keyed to the crop you pick.
Because it is a matrix, the same crop changes its answer as you move between cool, moderate and warm bands — spinach shifts from a spring sowing up north to an overwinter crop in the Gulf, exactly as any grower would expect. Nothing is computed, so there is no risk of a bad number; the job here is to surface the right window fast, then hand you to the date calculators when a precise calendar day matters more than the general rule.
Worked Example: Reading One Crop Across Zones
- Pick Spinach and choose the Cool zones 3–5 band.
- The window says sow as soon as soil is workable in April, and again in August.
- The season type confirms a hardy cool-season leaf that shrugs off light frost.
- Days to maturity reads about 45, so a late-July sowing matures before hard frost.
- Switch the same spinach to the Warm zones 8–10 band.
- Now the window flips to an October–November overwinter sowing.
- The reason is heat: spinach bolts the moment warm weather arrives up south.
- Repeat for a warm-season crop like tomato to see the opposite pattern.
- Cool zones delay tomato outdoors past mid-May; warm zones allow a February start.
- The whole plan falls out of two dropdowns and a frost-date confirmation.
Season Type by Crop at a Glance
The quick cool-versus-warm split that drives every planting window below, since warm-season crops wait for genuine heat while cool-season crops race the first frost. Read a crop's season here before trusting any single window, because the band flips the calendar entirely.
| Crop | Season | Typical days |
|---|---|---|
| Tomato | Warm | 80 |
| Pepper | Warm | 75 |
| Sweet Corn | Warm | 80 |
| Green Bean | Warm | 55 |
| Cucumber | Warm | 60 |
| Lettuce | Cool | 55 |
| Broccoli | Cool | 70 |
| Spinach | Cool | 45 |
Key Terms
- Zone band
- A grouping of USDA hardiness zones with similar season timing, used here to shape windows.
- Cool-season crop
- A vegetable that grows in mild weather, tolerates frost and bolts in summer heat.
- Warm-season crop
- A frost-tender crop that needs warm soil and air to germinate and bear.
- Days to maturity
- The average number of days from sowing or transplant to first harvest.
- Bolt
- When a cool-season crop runs to seed in heat, ending the harvestable stage.
Notes from Market Gardeners
- Zone numbers describe winter hardiness, not your planting dates, so treat the zone band as a season-shape hint and let your actual frost dates set the calendar.
- Cool-season crops give the best quality when they mature in cool weather, which is why fall plantings of broccoli and spinach often beat the spring crop in flavor.
- Warm-season direct sowings fail more often from cold soil than from late frost, so wait for the soil thermometer, not just the calendar, before dropping bean and corn seed.
- Succession sowing in two-week blocks turns a single-window crop like beans or lettuce into a continuous harvest without any extra beds.
- A single fast-maturing variety with the right season type covers more of the year than chasing a long list, because the window and days-to-maturity together decide whether a crop fits at all.
Common Mistakes and Fixes
- Reading a cool-zone window off a warm-zone guide and sowing weeks too early into cold soil.
- Treating USDA zones as planting dates when they actually describe minimum winter hardiness.
- Sowing spinach or lettuce in summer heat and blaming the seed when it simply bolts.
- Ignoring days to maturity and planting a long-season crop that cannot finish before frost.
- Direct-sowing warm crops the day of the last frost instead of waiting for warm soil.
- Relying on this general window when your site is a frost hollow or a sheltered warm wall.
When to Use This and When Not To
Use this calendar to sketch a season and learn each crop's general window and season behavior at a glance, especially early in planning before the specifics firm up. It gives rules of thumb rather than exact dates, so once a window matters, lock the real day with the frost-date, seed-starting and succession calculators, and adjust every answer here to your site's microclimate and your chosen variety's maturity.
Planting Calendar by Zone: Frequently Asked Questions
Are USDA zones the same as planting dates?
No. Zones describe average winter minimum temperature and hardiness, not when to sow. This calendar groups zones into broad bands only to shape a general window, but your local first and last frost dates are what actually set the precise planting day for your garden.
Why does the same crop show different windows by zone?
Because season length and heat drive timing. Spinach is a spring crop in cool zones but an overwinter crop in warm ones, since it bolts in heat, so the matrix changes the recommendation as you move between bands.
What are days to maturity counted from?
Usually from direct sowing for fast crops like beans and lettuce, and from transplanting for long-season crops like tomato and pepper. Always read the seed packet, because that reference point varies between catalogs and quietly shifts your whole schedule.
Can I use this instead of the seed-starting calculator?
This tool is the big-picture map of when each crop broadly belongs in the ground; the seed-starting and frost-date calculators then convert that general window into an exact calendar day for your specific location. Use them together rather than treating one coarse band as a substitute for the other.
How do microclimates change these windows?
A sheltered south wall, a frost pocket or a coastal influence can move any date by weeks in either direction. Treat the window here as the average and then nudge it using what you observe on your own site each spring.
Sources & Further Reading
- USDA Plant Hardiness Zone Map — USDA Agricultural Research Service. Basis for the cool, moderate and warm zone-band groupings.
- Vegetable Planting Guides by Zone — University of Vermont Extension. Source for cool-season and warm-season sowing windows and days to maturity.
- Succession Planting and Season Extension — Oregon State University Extension. Supports the fall-planting and overwintering guidance for cool-season crops.
Chlorova Gardening Team
Builds, checks and documents every tool we publish
Chlorova editorial review
Checked against extension-service publications
Formula verified against published references · Updated
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