Planning tool

USDA Zone and Frost-Date Planner

Compare USDA hardiness-zone temperature bands with local last-frost and first-frost dates so annual vegetable, herb, and flower timing is not reduced to zone alone.

Planning tool

Current zone and frost context

Zone 6B needs frost-date context

Zone 6B is winter context only. Choose a regional guide or local last-frost and first-frost dates before using planting calendars; keep ZIP lookup as a hardiness-only check.

Zone + frost map

Winter band Apr 15 last frost 183 days Oct 15 first frost

ZIP lookup explains winter hardiness; explicit frost dates drive annual crop timing.

USDA zoneZone 6B

Last frostApr 15

First frostOct 15

Season length183 frost-free days

Inputs

Regional frost dates first: Use source-backed regional frost-date presets before manual last-frost and first-frost editing.
ZIP lookup first: Use the built-in OSU PRISM ZIP artifact in the hydrated planner before manually choosing a USDA hardiness zone.
USDA hardiness zone: Manual fallback for average annual extreme minimum temperature bands and perennial survival context.
Last frost date: Manual fallback that controls spring direct-sow, indoor-start, and transplant timing for annual crops.
First frost date: Manual fallback that controls fall planting windows and expected season length.

What it returns

Regional frost-date preset status before zone-only hardiness context.
USDA half-zone temperature band context.
Season length from frost-date inputs.
Links into regional guides and season-specific catalog paths.

Lookup source decision

Recommended provider: USDA Plant Hardiness Zone Map
Build-time ZIP lookup: ready. Use the official USDA Plant Hardiness Zone Map as the user-facing source and the official OSU PRISM 2023 USDA Plant Hardiness Zone ZIP Code Listings as the build-time browser lookup artifact. Keep the manual USDA ZIP search visible, preserve attribution and caveats, and do not infer frost dates or planting windows from ZIP results.
Regional preset path: Hydrated users can apply source-backed regional frost-date presets before manual date editing.
Lookup artifact: /data/usda-phzm-zip-lookup.json with 39,921 ZIP records.
Artifact dataset: OSU PRISM 2023 USDA Plant Hardiness Zone ZIP Code Listings
Integration rule: Use only a documented API or official USDA/OSU GIS data pipeline for automated ZIP or coordinate lookup; the current ZIP lookup uses the official OSU PRISM ZIP Code Listings artifact.
Hardiness-zone limitation: Hardiness zones describe average annual extreme minimum winter temperature, not last frost dates, first frost dates, soil temperature, or annual vegetable planting windows.

USDA/OSU GIS guardrails

Pipeline status: Status: design-only. Browser lookup uses a committed build-time artifact from official OSU PRISM ZIP listings.
ZIP artifact source: OSU PRISM 2023 USDA Plant Hardiness Zone ZIP Code Listings: https://prism.oregonstate.edu/phzm/data/2023/phzm_us_zipcode_2023.csv
ZIP artifact caveat: ZIP Code listings are not parcel-level hardiness-zone results; local microclimates, elevation, and ZIP boundaries can differ from a garden site.
ZIP artifact boundary: Do not infer last frost dates, first frost dates, or planting windows from the ZIP result.
Data inputs: Use only official USDA/OSU or PRISM GIS data for automated lookup, including the 2023 grid, shapefile, raster, or ZIP-code datasets described by USDA.
Processing: Process GIS data offline or at build time into a small read-only lookup artifact; do not call interactive map requests from the browser.
Attribution: Show USDA-ARS and OSU attribution when presenting data or maps derived from the official GIS datasets.
Frost-date boundary: Return hardiness-zone results separately from frost-date planning; do not infer last frost dates, first frost dates, or planting windows from a zone result.
Result contract: Show the resolved USDA half-zone and average annual extreme minimum temperature band without deriving crop timing. Show USDA-ARS and OSU attribution next to the result whenever derived PHZM GIS data is used. Show ZIP boundary, centroid, and microclimate caveats near the result so gardeners do not treat the ZIP result as parcel-level advice. Keep the manual USDA ZIP search link available as a fallback next to automated results.
Blocked approach: Do not scrape undocumented ArcGIS, iframe, or browser network requests from the interactive USDA map.

Regional guide fallback

Regional Planting Guides Use the regional guide index when a ZIP result is too broad; 111 source-backed regional guides cover All 50 U.S. states.

Regional timing paths

Alabama Seasons 25 catalog crop examples
Alameda East Bay 28 catalog crop examples
Alaska Short Season 12 catalog crop examples
Arizona Elevation Bands 30 catalog crop examples
Arkansas Fall 17 catalog crop examples
Arkansas Zone C 26 catalog crop examples
Butte Foothills 22 catalog crop examples
California Interior Valley 25 catalog crop examples
Central Florida 10 catalog crop examples
Central Maryland 25 catalog crop examples
Central Missouri 11 catalog crop examples
Central NH 31 catalog crop examples
Central Oregon Seeds 15 catalog crop examples
Chicago Area IL 20 catalog crop examples
Colorado Front Range 8 catalog crop examples
Colorado Containers 19 catalog crop examples
Colorado Mountains 25 catalog crop examples
Connecticut Calendar 30 catalog crop examples
Contra Costa Interior 18 catalog crop examples
Delaware Frost 25 catalog crop examples
East Texas 28 catalog crop examples
Eastern NC 32 catalog crop examples
Eastern Oregon Seeds 20 catalog crop examples
Georgia 17 catalog crop examples
Georgia Varieties 11 catalog crop examples
Harris County 34 catalog crop examples
Hawaii Elevations 13 catalog crop examples
Idaho Zones 27 catalog crop examples
Illinois 21 catalog crop examples
Indiana Frost/Soil 32 catalog crop examples
Iowa Timing 10 catalog crop examples
Kansas Calendar 36 catalog crop examples
Kauai County 19 catalog crop examples
Kentucky Regions 29 catalog crop examples
Long Island 18 catalog crop examples
Louisiana North/South 12 catalog crop examples
Michigan LP 20 catalog crop examples
Maine Coast/North 17 catalog crop examples
Maricopa County 36 catalog crop examples
Marin Monthly 28 catalog crop examples
Massachusetts 35 catalog crop examples
McHenry County IL 28 catalog crop examples
Middle Georgia 20 catalog crop examples
Minnesota Soil Temp 33 catalog crop examples
Mississippi Zones 27 catalog crop examples
Missouri Varieties 14 catalog crop examples
Montana Frost Windows 27 catalog crop examples
Napa County 20 catalog crop examples
Nebraska Frost/Soil 25 catalog crop examples
New Jersey Frost 21 catalog crop examples
New Mexico Zones 17 catalog crop examples
NYC Area 35 catalog crop examples
NC Piedmont 17 catalog crop examples
North Dakota Small Space 16 catalog crop examples
North Florida 26 catalog crop examples
North Missouri/Ozark 12 catalog crop examples
Northern Nevada 20 catalog crop examples
Northern Wisconsin 32 catalog crop examples
Central Ohio 32 catalog crop examples
Oklahoma Fall 18 catalog crop examples
Oklahoma Planning 22 catalog crop examples
Orange County Small Space 27 catalog crop examples
Oregon Coast 27 catalog crop examples
Oregon Regions 8 catalog crop examples
Philadelphia Area 34 catalog crop examples
Pima County 41 catalog crop examples
Placer County 26 catalog crop examples
Rhode Island Calendar 31 catalog crop examples
Rockwall County 28 catalog crop examples
Sacramento Area 32 catalog crop examples
San Diego County 25 catalog crop examples
SLO Cool Season 24 catalog crop examples
SF/San Mateo 29 catalog crop examples
Santa Clara County 42 catalog crop examples
Shasta County Valley 31 catalog crop examples
Sonoma Planting 39 catalog crop examples
South Carolina 29 catalog crop examples
South Dakota Frost/Soil 22 catalog crop examples
South Florida 22 catalog crop examples
South Missouri 14 catalog crop examples
SE Wisconsin 31 catalog crop examples
Southern Nevada Desert 28 catalog crop examples
Tennessee Cool Season 6 catalog crop examples
Tennessee Warm Season 6 catalog crop examples
Texas Fall 21 catalog crop examples
Texas Home Garden 27 catalog crop examples
Travis County 30 catalog crop examples
Tulare/Kings Valley 29 catalog crop examples
Upper Midwest 8 catalog crop examples
Michigan UP 20 catalog crop examples
Upstate New York 26 catalog crop examples
Utah Frost Groups 29 catalog crop examples
Utah Varieties 6 catalog crop examples
Ventura County 36 catalog crop examples
Vermont Frost 22 catalog crop examples
Virginia Zones 27 catalog crop examples
Walla Walla Inland NW 21 catalog crop examples
Wasatch Front 31 catalog crop examples
Washington County Fall 15 catalog crop examples
Washington County UT 14 catalog crop examples
Western Washington 23 catalog crop examples
West Virginia 33 catalog crop examples
Western NC 40 catalog crop examples
Willamette Calendar 40 catalog crop examples
Wisconsin Containers 13 catalog crop examples
Wyoming Statewide 9 catalog crop examples
Midwest Native Pollinators 7 catalog crop examples
Yolo County Spring 9 catalog crop examples
York County PA 8 catalog crop examples
York County Seeds 21 catalog crop examples
Yuma County 38 catalog crop examples

Season paths

Cool Season Seeds Crops that can fit spring or fall windows
Warm Season Seeds Crops that need frost-free warmth
Shoulder Season Seeds Flexible crops between cool and warm windows
Fall Planting Planner 63 first-frost-window varieties
Fall-Planting Seeds 63 first-frost-window varieties

Fall-window examples

Long Island Improved Brussels Sprouts 16 weeks before first frost
American Flag Leek 14 weeks before first frost
American Purple Top Rutabaga 12 weeks before first frost
Golden Acre Cabbage 12 weeks before first frost
Marketmore 76 Cucumber 12 weeks before first frost
Snowball Y Cauliflower 12 weeks before first frost

Source basis

USDA Plant Hardiness Zone Map Official 2023 USDA PHZM site with interactive map and user-facing ZIP Code search
USDA PHZM Map Creation Explains GIS data ownership, attribution conditions, ZIP finder, and 1991-2020 normals
OSU PRISM 2023 PHZM GIS datasets Official OSU PRISM page for 2023 PHZM grid, shapefile, KML, and ZIP Code Listing datasets
OSU PRISM 2023 PHZM ZIP Code Listings CSV Official CSV listing ZIP Code, USDA half-zone, temperature range, and zone title for build-time lookup
USDA Ag Data Commons 2023 PHZM rasters Official 2023 raster dataset for future GIS-based zone lookup work
USDA PHZM How to Use the Maps Describes ZIP search, map use, hardiness-zone limits, and microclimate caveats
UMN planting the vegetable garden Upper Midwest regional timing source
UMN planting the vegetable garden Minnesota Soil Temp regional timing source
OSU Extension Planning for the Garden Central Ohio regional timing source
CSU vegetable planting guide Colorado Front Range regional timing source
CSU Extension vegetable gardening in containers Colorado Containers regional timing source
CSU Extension vegetable gardening in the mountains Colorado Mountains regional timing source
UW Extension Waukesha County Vegetable Garden Planting Schedule SE Wisconsin regional timing source
UW-Madison Extension Vegetable Varieties for Containers Wisconsin Containers regional timing source
UW Extension Planting guide for northern Wisconsin Northern Wisconsin regional timing source
University of Wyoming Extension Growing Vegetables in Wyoming Wyoming Statewide regional timing source
UVM Extension Master Gardener Planting the Garden Vermont Frost regional timing source
University of Delaware Cooperative Extension Planning a Vegetable Garden Delaware Frost regional timing source
Rutgers NJAES Starting Vegetable Seeds Indoors New Jersey Frost regional timing source
URI Cooperative Extension Rhode Island Planting Calendar Rhode Island Calendar regional timing source
UConn Connecticut Vegetable Crop Calendar Connecticut Calendar regional timing source
Cornell Vegetables planting dates for Upstate New York Upstate New York regional timing source
CCE Suffolk Vegetable Planting Times Guidelines for Long Island Long Island regional timing source
Cornell Cooperative Extension Harvest NY Planting Guide for the New York City Area NYC Area regional timing source
University of Idaho Extension Spring Vegetable Planting Guide for Idaho Idaho Zones regional timing source
MSU Extension Upper Peninsula Michigan Gardening Calendar Michigan UP regional timing source
MSU Extension Lower Peninsula Michigan Garden Calendar Michigan LP regional timing source
OSU Extension vegetable gardening in Oregon Oregon Regions regional timing source
OSU Extension An educator's guide to vegetable gardening Willamette Calendar regional timing source
OSU Extension Eastern Oregon seed-starting schedule Eastern Oregon Seeds regional timing source
OSU Extension When to start seeds indoors in central Oregon Central Oregon Seeds regional timing source
OSU Extension The best vegetables to grow in Oregon's coastal climate Oregon Coast regional timing source
Clemson Extension planning a garden South Carolina regional timing source
UA Extension vegetable planting calendar for Maricopa County Maricopa County regional timing source
Ten Steps to a Successful Vegetable Garden Arizona Elevation Bands regional timing source
UA Cooperative Extension Yuma County Planting and Harvesting Calendar Yuma County regional timing source
UA Cooperative Extension Pima County Vegetable Planting and Harvesting Guide Pima County regional timing source
UF/IFAS Florida Vegetable Gardening Guide Central Florida regional timing source
UF/IFAS Florida Vegetable Gardening Guide South Florida regional timing source
UF/IFAS Florida Vegetable Gardening Guide North Florida regional timing source
UH CTAHR Planting, Harvest Periods and Spacing of Vegetables Kauai County regional timing source
UH Bulletin 91 Home Gardening in Hawaii Hawaii Elevations regional timing source
Penn State York County vegetable transplanting guide York County PA regional timing source
Penn State York County vegetable seed planting guide York County Seeds regional timing source
Penn State Master Gardeners Philadelphia Planting Guide Philadelphia Area regional timing source
MU Extension vegetable planting calendar Central Missouri regional timing source
MU Extension vegetable planting calendar North Missouri/Ozark regional timing source
MU Extension vegetable planting calendar South Missouri regional timing source
MU Extension vegetable planting calendar Missouri Varieties regional timing source
NC State Extension estimated planting dates for the NC Piedmont NC Piedmont regional timing source
NC State Extension Eastern North Carolina Planting Calendar for Annual Vegetables, Fruits, and Herbs Eastern NC regional timing source
NC State Extension Western North Carolina Planting Calendar for Annual Vegetables, Fruits, and Herbs Western NC regional timing source
UGA Extension vegetable planting chart Georgia regional timing source
UGA Extension Best Garden Vegetable Varieties for Georgia Georgia Varieties regional timing source
UGA Extension Vegetable Garden Calendar Middle Georgia regional timing source
Oklahoma State University Extension Oklahoma Garden Planning Guide Oklahoma Planning regional timing source
OSU Extension fall gardening Oklahoma Fall regional timing source
Illinois Extension when to plant Illinois regional timing source
Illinois Extension when to plant Chicago Area IL regional timing source
Illinois Extension McHenry County vegetable garden planting guide McHenry County IL regional timing source
Texas A&M AgriLife fall vegetable gardening guide Texas Fall regional timing source
Texas A&M AgriLife Texas Home Vegetable Gardening Guide Texas Home Garden regional timing source
Texas A&M AgriLife Travis County Vegetable Garden Planting Guide Travis County regional timing source
Texas AgriLIFE Extension Service Harris County Vegetable Garden Planting Dates Harris County regional timing source
Rockwall County Master Gardeners Vegetable Planting Guide Rockwall County regional timing source
Henderson County Master Gardeners East Texas Vegetable Planting Guide East Texas regional timing source
UC Master Gardener Contra Costa interior vegetable planting guide Contra Costa Interior regional timing source
UC Master Gardener Program Time of planting California Interior Valley regional timing source
UC ANR Cooperative Extension Ventura County Planting Vegetables Ventura County regional timing source
UC Master Gardeners San Mateo and San Francisco Edible Gardening and Planting Calendars SF/San Mateo regional timing source
UC Master Gardeners of Santa Clara County Vegetable Planting Chart Santa Clara County regional timing source
UC Master Gardener Program of Alameda County Growing Vegetables Alameda East Bay regional timing source
UC Master Gardeners of San Luis Obispo County Cool Season Vegetable Guide SLO Cool Season regional timing source
UC Master Gardener Program of Sonoma County Vegetable Planting Summary Sonoma Planting regional timing source
UC Master Gardeners of Placer County Growing Vegetables in Placer County Placer County regional timing source
UC Master Gardeners of Tulare and Kings County Vegetable Planting Guide Tulare/Kings Valley regional timing source
UC Master Gardeners of Napa County Vegetable Planting Calendar Napa County regional timing source
UC Master Gardeners of Sacramento County Vegetable Planting Schedule Sacramento Area regional timing source
UC ANR The Savvy Sage April Vegetable Planting Guide Yolo County Spring regional timing source
UC ANR Shasta County Monthly Planting Guide Shasta County Valley regional timing source
UC Master Gardeners of Orange County Small Spaces Orange County Small Space regional timing source
UC Master Gardeners of Butte County Foothill Planting Guide Butte Foothills regional timing source
UC Marin Master Gardeners Edible Garden Monthly Planting & Maintenance Schedule Marin Monthly regional timing source
UC Agriculture and Natural Resources San Diego County Vegetable Planting Guide San Diego County regional timing source
NMSU growing zones and planting information for New Mexico home vegetable gardens New Mexico Zones regional timing source
UAF Cooperative Extension 16 Easy Steps to Gardening in Alaska Alaska Short Season regional timing source
UMaine Extension planting chart for the home vegetable garden Maine Coast/North regional timing source
USU suggested vegetable planting dates for Utah Utah Frost Groups regional timing source
USU Suggested Vegetable Planting Dates For the Wasatch Front Wasatch Front regional timing source
USU Extension Washington County Vegetable Gardening Washington County UT regional timing source
USU Extension Washington County Fall Vegetable Garden Calendar Washington County Fall regional timing source
USU Extension Home Vegetable Garden: Variety Recommendations for Utah Utah Varieties regional timing source
MSU Extension Can I Grow That Here? Montana Frost Windows regional timing source
UNR Extension getting started with a vegetable garden Northern Nevada regional timing source
UNR Extension Becoming a Desert Gardener Southern Nevada Desert regional timing source
UMD Extension Vegetable Planting Calendar Central Maryland regional timing source
UNH Extension growing vegetables when to plant your vegetable garden Central NH regional timing source
UMass Extension Vegetable Planting Chart Massachusetts regional timing source
WVU Extension Succession Planting West Virginia regional timing source
MSU Extension Planting Dates Mississippi Zones regional timing source
Purdue Extension Indiana Vegetable Planting Calendar Indiana Frost/Soil regional timing source
K-State Research and Extension Vegetable Garden Planting Guide Kansas Calendar regional timing source
Virginia Cooperative Extension Home Garden Vegetable Planting Guide Virginia Zones regional timing source
UAEX Arkansas spring and summer vegetable planting dates Arkansas Zone C regional timing source
UAEX Arkansas fall vegetable planting dates Arkansas Fall regional timing source
Iowa State University Extension Planting and Harvesting Times for Garden Vegetables Iowa Timing regional timing source
University of Kentucky Home Vegetable Gardening in Kentucky Kentucky Regions regional timing source
Alabama Extension Vegetable Seasons in Alabama Alabama Seasons regional timing source
LSU AgCenter Louisiana Vegetable Planting Guide Louisiana North/South regional timing source
UT Extension Guide to Warm-Season Garden Vegetables Tennessee Warm Season regional timing source
UT Extension Guide to Spring-Planted Cool-Season Vegetables Tennessee Cool Season regional timing source
SDSU Extension Vegetable Gardening in South Dakota South Dakota Frost/Soil regional timing source
Nebraska Extension Selecting and Preparing Vegetables, Herbs, and Fruit Nebraska Frost/Soil regional timing source
NDSU Extension Pickin' Patch small-space vegetable gardening North Dakota Small Space regional timing source
Xerces Native Plants for Pollinators and Beneficial Insects: Midwest Midwest Native Pollinators regional timing source
WSU Extension Home Vegetable Gardening in Washington Western Washington regional timing source
WSU Walla Walla Inland Northwest Vegetable Gardening Walla Walla Inland NW regional timing source