University Park, Iowa, sits in USDA hardiness zones 5a-6b — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
Reliable performers under these conditions include sweet corn, tomato, apple, and grape; what your own ground favors still comes down to its soil, sun, and drainage.
Even in University Park, 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 University Park lot. Enter your address and we'll score 1,112 plants against your land's actual soil, sun, and frost.
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
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Quick Facts
USDA Zones
5a-6b
Last Hard Freeze (28°F)
Mar 26
Town normal — light frosts run a few weeks later
First Hard Freeze (28°F)
Nov 11
Town normal — light frosts arrive a few weeks earlier
City Area
498 acres
Hardiness Zone Range
Zone maps are averages across University Park. Your yard's slope, trees, and frost pockets shift what actually grows — see your land's exact reading.
Soil varies lot by lot — soil types explained.
What Grows in University Park
Plants matched to University Park's USDA zones 5a-6b — each links to its full growing profile.





Is it too late to plant in University Park?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Feb 26; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 26 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 11 — 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.

Growing Challenges in Iowa
What an experienced grower plans around here — each one has a move.

Cold winters reaching -20F or below
Choose perennials rated a zone hardier than yours — Iowa winters test the margins, and the margin is where plants are lost.

Variable spring weather delays planting
Let soil temperature and your local frost normal call the start, not the calendar — a two-week wait beats a replant.

Wind exposure on open prairies desiccates plants
Even a simple windbreak — a shrub row, a snow fence, a tall cover crop — cuts wind desiccation dramatically.
For cultivar selection, pest pressure, and planting-time guidance specific to Iowa, the Iowa State University Extension and Outreach is the authoritative local source.
Environmental Intelligence
Understanding what's nearby helps you make informed decisions about where and how to grow.
Sources Checked
within ~10 miles of University Park
Severity Distribution
within ~10 miles of University Park
Highest-Severity Sites

A note from Gnorman
What an experienced grower watches for around here
In and around University Park, two things run higher than the national average — Nitrate (66 sites) and Toxic Release Inventory (14 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.
Toxic 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 University Park
Get exact proximity distances to contamination sources for your specific parcel — plus soil, sun, drainage, and 1,112 plant recommendations.
Three things about your exact spot that zone averages miss:
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources analyzed in seconds
Your Specific Parcel Matters
University Park Average
- ●USDA Zones 5a-6b
- ●Generic soil type for the area
- ●State-average frost dates
YOUR Parcel
- ✓Your exact hardiness zone
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in University Park
Pull a site-specific report for your exact address in University Park, Iowa — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your exact spot that zone averages miss:
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources analyzed in seconds
Key Growing Facts for University Park, Iowa
- USDA Hardiness Zones: 5a-6b (USDA PHZM 2023)
- Last Hard Freeze (28°F): Mar 26 (town normal, NOAA 1991–2020 Climate Normals — light frosts can follow for a few weeks)
- First Hard Freeze (28°F): Nov 11 (town normal, NOAA 1991–2020 Climate Normals — light frosts can arrive a few weeks earlier)
- Days Between Hard Freezes: ~230 (town normal, NOAA 1991–2020 Climate Normals)
- Land Area: 498 acres (US Census TIGER 2025)
Zone data: USDA ARS Plant Hardiness Zone Map 2023. Climate data: NOAA NCEI. Boundaries: US Census TIGER/Line 2025.
Frequently Asked Questions
What hardiness zone is University Park, Iowa?
University Park sits in USDA hardiness zones 5a-6b, per the USDA Plant Hardiness Zone Map 2023. Zones reflect average annual extreme minimum temperatures from 1991–2020 weather data.
Is it too late to plant in University Park?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Feb 26; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 26 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 11 — 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.
When does frost risk typically end in University Park?
The last hard freeze (28°F) in University Park typically lands around Mar 26, per NOAA 1991–2020 climate normals — an earlier marker than the light-frost dates many planting charts quote. That marks the hard freeze, not the last light frost — light frosts can still bite for a few more weeks, so tender transplants usually wait another 2–3 weeks.
When is the first frost in University Park?
The first hard freeze (28°F) in University Park typically arrives around Nov 11, per NOAA 1991–2020 climate normals — the point most tender summer crops finish. Lighter frosts usually reach a couple of weeks earlier, so watch the forecast from late summer on and harvest or cover tender plants before the first cold night.
What vegetables grow in University Park?
University Park's zones 5a-6b support a wide range — strong performers include Sweet Corn, Tomato, Apple, Grape, and Hosta. What actually takes on any one site comes down to its soil, sun, and drainage, and we score each plant against the real conditions at your address.
Which hardiness zone is University Park, really?
Officially, University Park sits in USDA zones 5a-6b (USDA PHZM 2023) — but a zone is a 30-year average of winter's coldest night across an area, and it can't see any one yard. A south-facing slope, a tree line, or a low frost pocket can shift a single site by half a zone either way, which is why neighboring gardeners often quote different numbers. We read the conditions at your exact address — soil, sun, slope, and frost — and score 1,112 plants against what's actually there.
Is the soil safe to grow vegetables in University Park?
The federal record around University Park is a meaningful one — 212 documented sites — 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 University Park?
As the season closes around the first 28°F hard freeze near Nov 11 (NOAA 1991–2020 climate normals), a few moves buy time: cover tender plants with floating row cover or an old sheet on still, clear nights, water the soil the afternoon before a freeze so it holds warmth overnight, and harvest frost-tender crops like tomatoes, peppers, and basil before the first hard night. Hardy greens and root crops shrug off light frost and often sweeten after it, so leave them in.
Everything on this page is a University Park average. Your yard writes its own version — we read soil, sun, drainage, and frost at your exact address. Try it for 14 days — no card required.
