Growli frost calendar — 2026
Frost dates by USDA zone
— last & first frost guide
What frost dates tell you
The last spring frost is the green light for planting tender crops outdoors; the first fall frost is the deadline that ends the warm-season harvest. Knowing both lets you start seeds indoors at the right time, transplant safely, and protect or harvest before the cold returns.
How to use this hub
Find your USDA zone in the table below and open its frost-date page for the last spring frost, first fall frost, frost-free days, and the tender crops to sow once frost has passed. For an address-precise estimate, use the frost-date calculator.
Frost dates for all 13 USDA zones
| Zone | Last spring frost | First fall frost | Frost-free days | Frost-date page |
|---|---|---|---|---|
| Zone 1 | mid-June | mid-August | ~60 | Zone 1 frost dates → |
| Zone 2 | early June | late August | ~90 | Zone 2 frost dates → |
| Zone 3 | late May | early September | ~110 | Zone 3 frost dates → |
| Zone 4 | mid-May | mid-September | ~125 | Zone 4 frost dates → |
| Zone 5 | late April / early May | late September / early October | ~150 | Zone 5 frost dates → |
| Zone 6 | mid- to late April | mid- to late October | ~180 | Zone 6 frost dates → |
| Zone 7 | mid-April | late October / early November | ~200 | Zone 7 frost dates → |
| Zone 8 | mid- to late March | mid-November | ~230 | Zone 8 frost dates → |
| Zone 9 | mid-February to early March | late November / early December | ~280 | Zone 9 frost dates → |
| Zone 10 | frost rare or never | frost rare or never | ~365 | Zone 10 frost dates → |
| Zone 11 | no frost | no frost | ~365 | Zone 11 frost dates → |
| Zone 12 | no frost | no frost | ~365 | Zone 12 frost dates → |
| Zone 13 | no frost | no frost | ~365 | Zone 13 frost dates → |
Frost-date averages: NOAA Climate Data Online national averages. Local ZIP-code-precise dates can vary by one to three weeks from these zone midpoints.
Don't know your zone?
The frost table is most useful once you know which row applies to you. Use the Growli zone finder to look up your USDA zone (or UK RHS rating) from your ZIP code or postcode in seconds.
Frequently asked questions
What is a frost date?
A frost date is the average calendar date for the last freezing night in spring (last spring frost) or the first freezing night in fall (first fall frost). It is a 30-year statistical average, not a guarantee — roughly half the years frost comes earlier and half later.
Why do frost dates matter more than the calendar?
Tender crops like tomatoes, peppers, and basil die at or just below 32°F (0°C). Frost dates tell you the safe window to plant them out in spring and the deadline to harvest or protect them in fall — far more useful than a fixed calendar date.
How accurate are zone-average frost dates?
They are good planning anchors but not address-precise. Microclimates — south-facing slopes, urban heat islands, frost pockets, lakeside warmth — can shift your real dates by one to three weeks from the zone average.
How do I find my exact frost dates?
Use the Growli frost-date calculator with your US ZIP code or UK postcode for a closer estimate, then track your own first and last frosts each year to refine it for your specific yard.
Do all USDA zones have frost?
No. USDA zones 10-13 are effectively frost-free tropical or subtropical climates where heat tolerance, not cold, is the limiting factor for what you can grow.