Harper, Kansas, sits in USDA hardiness zone 7a — a zone band wide enough that plant choice, not possibility, is the interesting question.
Reliable performers under these conditions include cabbage, hazelnut, california poppy, and collard greens; what your own ground favors still comes down to its soil, sun, and drainage.
Even in Harper, no two yards are alike.
A low spot, a south-facing slope, or a stand of trees moves the frost date and sun across a single Harper lot. Enter your address and we'll score 1,086 plants against your land's actual soil, sun, and frost.
We read public map data around Harper — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Harper — the short answer
Harper, Kansas: USDA zone 7a, about 226 days between hard freezes, across 1K acres of city.
- USDA zone
- 7a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 29
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 10
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~226
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 1K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. Hard-freeze dates are this town’s own 28°F normals: light frosts run a few weeks past them, and tender transplants usually wait 2–3 weeks after the last hard freeze.
Hardiness Zone Range
Zone 7a is Harper's average, not your lot's — a low corner or a tree line moves it. Against Harper's 226-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Harper
Each reading below is measured for Harper itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredHarper runs about 226 days between hard freezes — a long growing season.
There is slack for succession plantings and slow-finishing crops: many vegetables can be sown twice, and the heat-lovers have time to ripen fully.
Plan a second sowing of quick crops after the first comes out, and use the fall window most gardeners let sit idle.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredHarper sits in USDA hardiness zone 7a.
The zone sets which perennials, shrubs, and fruit trees live through an average winter here — a plant rated for a colder zone is a safe bet, one rated warmer needs winter protection or gets treated as an annual.
Match perennials and fruit to the zone before you buy, so nothing you plant is a gamble against the cold.
USDA PHZM 2023
The kind of country Harper is in
Harper sits in the Central Great Plains — EPA Level III, inside the wider Great Plains. That is read at Harper's own centroid rather than borrowed from Harper County.
What Grows in Harper
Every plant below cleared Harper's own zone 7a and its 226-day season. Each card opens that plant's Kansas profile. How we score.
Is it too late to plant in Harper?
Too late for some crops, right on time for others — a growing season is a sequence, not a deadline. Cool-season crops can go in from around Mar 1; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 29 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 10 — long-season crops need about 90 days of runway, quick greens only 30. Here the season winds down slowly: late sowings, a real autumn harvest, and garlic in the ground before the first hard freeze.
What's on the federal record near Harper
Closest first, within ~10 miles of Harper. Listing isn't leaking, and distance isn't exposure.
- MONFORT INCBrownfields · 750 ft
- CASEY'S GENERAL STORE - #2955Underground Storage Tanks · 850 ft
- MILLS WELDING SVCBrownfields · 850 ft
- HIGRADE SAND COBrownfields · 850 ft
- ANTHONY FARMERS COOP SERV STATUnderground Storage Tanks · 1200 ft
- CASEY'S GENERAL STORE #3063Underground Storage Tanks · 1300 ft
- SAV-A-TRIP, INC. #25Underground Storage Tanks · 1400 ft
- HARPER SVC CTRBrownfields · 1400 ft
- ELM TREE GARAGEBrownfields · 1600 ft
- ET AUTOMOTIVEBrownfields · 1700 ft
- REIFORD ACORDBrownfields · 1900 ft
- RONS SERVICE %FIRST NATIONAL BUnderground Storage Tanks · 1900 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Harper's center, not your beds. Run your own address for what's upwind of you specifically.
Environmental Intelligence
The counts behind that headline — every source type on the record near Harper.
Total Sites
107
within ~10 miles of Harper
Risk Level
Elevated
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
within ~10 miles of Harper
Severity Distribution
within ~10 miles of Harper
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Harper, two things run higher than the national average within ~10 miles of Harper — Nitrate (38 sites) and Toxics Release Inventory (7 sites). It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Toxics Release Inventory: TRI facilities report annual chemical releases to air, water, and land.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check prevailing wind direction — downwind parcels face higher exposure than upwind or crosswind locations.
Check your specific parcel in Harper
Get exact proximity distances to contamination sources for your specific parcel — plus soil, sun, drainage, and 1,086 plant recommendations.
25+ data sources read at your address, not the Harper average
Your land is one point inside Harper
Everything above resolves to Harper as a whole — one PHZM band and one 28°F frost record, read across 1K acres. Your parcel is one point inside that footprint. Slope, tree cover, a low spot that pools cold air, and what is in the soil are all resolved at the address, and none of them are visible at city scale. That is the honest boundary of this page, and the reason the next step is a reading of your own ground rather than a better local average.
Your Lot vs the Harper Average
Harper Average
- ●USDA Zones 7a, averaged across Harper
- ●One soil character for all of Harper
- ●Frost dates read at Harper's scale: Mar 29 to Nov 10
YOUR Parcel
- ✓Your exact zone, not Harper's 7a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Harper
Pull a site-specific report for your exact address in Harper, Kansas — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Harper averages can't show:
We read public map data around Harper — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Harper average
How we know this about Harper
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this city’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Harper’s own record; boundaries and acreage from US Census TIGER/Line 2025; the contamination records from the federal sources named in their beats above. Soil is not read at city grain anywhere on this page — there is no city-resolution survey in our data, which is why you will find no soil grid here rather than a statewide one wearing a local label. The resolution ledger below names every figure this page inherited.
Common questions about Harper
When does frost risk typically end in Harper?
The last hard freeze (28°F) in Harper typically lands around Mar 29, per NOAA 1991–2020 climate normals — earlier than the light-frost dates most charts quote. That marks the hard freeze, not the last light frost — lighter frosts keep biting past it, which is why tender transplants here wait until about Apr 19.
When is the first frost in Harper?
The first hard freeze (28°F) in Harper typically arrives around Nov 10, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 27, so the watching starts about Oct 11 — about 226 days after the spring freeze cleared.
How long is the growing season in Harper?
Measured between 28°F hard freezes, Harper sees about 226 frost-free days — roughly Mar 29 through Nov 10, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 19 to Oct 27, about 191 days.
Is the soil safe to grow vegetables in Harper?
The federal record around Harper is a meaningful one — 107 documented sites, mostly Nitrate entries (38), the nearest Brownfields record about 0.1 miles out — so a soil test before new food beds is a sensible precaution here, not a reason to hold back from growing. Remember that proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what sits where.
How do I protect my plants from frost in Harper?
From about Oct 11 the job here turns from planting to protecting — the last start even a 30-day crop can finish. As the season closes around the first 28°F hard freeze near Nov 10 (NOAA 1991–2020 climate normals), three moves buy time: row cover or an old sheet over tender plants on still, clear nights; water the soil the afternoon before a freeze, so it holds warmth overnight; and harvest tomatoes, peppers and basil before Nov 10. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Harper's scale — its 7a band and its 226-day season. Your yard writes its own version of Harper's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
What this page reads at Harper’s own scale
6 of the readings below were taken at Harper's own scale — its own ~226-day season between 28°F freezes, the 1,039 acres it covers and 107 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Harper's own USDA hardiness band, zones 7aUSDA PHZM 2023
- Harper's own 28°F hard-freeze dates, about Mar 29 and Nov 10 and the ~226-day span between themNOAA 1991–2020 Climate Normals
- 107 documented contamination sites on the federal record near Harper, the closest Brownfields record about 0.1 miles out from the town centreFederal environmental registers
- Harper's boundary and the 1,039 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7a and a ~226-day seasonGrowable Ground crop-matching engine
- The ecoregion at Harper's own centroid, the Central Great PlainsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Harper's 1,039 acres read through its county's SSURGO summaryfrom Harper County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Harper County
- The growing challenges every Kansas grower plans around — written at state scale, so they stay on the state guidefrom Kansas
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Harper County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Harper's 1,039 acreswhy one lot differs from the next →
- Which side of Harper you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 1,039 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Brownfields record about 0.1 miles out, measured from the town centrehow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — measured at your address, and averaged away by any Harper-wide figureread your own land →