Conditional — Some Areas
willow oak (zones 5-9) reaches only part of Minnesota (3a-5a): zone 5 are in range, so where you are in the state decides it.
Willow Oak in Minnesota — the short answer
Willow Oak in Minnesota: hardy in zones 5–9, part sun, against a state median of ~174 frost-free days.
- Plant zones
- 5-9
- Manual horticultural correction (source not retained); NC State Extension and Missouri Botanical Garden, with the remaining rows from other published sources or Growable Ground compilation
- Minnesota zones
- 3a-5a
- USDA PHZM 2023
- Frost window
- Apr 19 - Apr 30 – Oct 10 - Oct 17
- NOAA RCC ACIS 1991-2020, 28°F
- Shortest county season
- 137 days
- NOAA Regional Climate Centers ACIS, 1991-2020, county 28°F killing freeze
Plant data: Growable Ground Plant Database, compiled from FAO ECOCROP, USDA PLANTS and university Extension sources — per-field provenance varies and is published with the dataset.
Your yard isn't the whole zone.
Minnesota spans zones 3a-5a, but your yard sits in exactly one — and slope, tree cover, and cold-air pockets nudge it further. Enter your address and we'll score willow oak against your parcel's actual hardiness, soil, and sun.
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Minnesota is not one climate
Minnesota’s winter-low ladder runs across 87 counties, from zone 3.5 in Beltrami County to zone 5 in Watonwan County. That is 15°F between the two counties’ average coldest night — the difference between willow oak overwintering in the ground and coming under cover.
The middle half of 87 counties runs 4–4.5 zones, with a median of 4.5 zones — a 1.5-zone span end to end.
Measured across 87 Minnesota counties. USDA PHZM 2023, per county. Quartiles are order statistics — every figure shown is a value a real county recorded, not an interpolation. Your own site sits somewhere inside this range; a parcel report resolves where.
Where in Minnesota Fits Best
Willow Oak is rated for zones 5–9 — a cold floor USDA puts at -20 to -10°F. Against Minnesota’s 87 counties that band holds in 18 of them, and the line runs at Blue Earth County (zone 5a), the coldest county still inside it.
Inside zones 5–9
18 counties
- Brown County · zone 5a
- Cottonwood County · zone 5a
- Dakota County · zone 5a
3 of 18 shown
Below the zone 5 floor
69 counties
- Beltrami County · zone 3b
- Clearwater County · zone 3b
- Hubbard County · zone 3b
3 of 69 shown
Winter cold is the limit here — the same plant works in a container that comes under cover.
County hardiness zones: USDA Plant Hardiness Zone Map (PHZM) 2023, per county. A zone is a 10°F band of average annual extreme minimum temperature, so the floor above is the band the plant's rating denotes, not a single measured kill point. Slope, shelter and cold-air drainage routinely move a site half a zone either way from its county figure — which is the part only your address resolves.
Even within Minnesota's zones 3a-5a, county microclimates differ enough to change what thrives. These counties carry the closest zone match for willow oak (USDA PHZM 2023):
Zone Comparison
Willow Oak Needs
- USDA Zones: 5-9
- Sun: Part Sun
- Mature size: 60 ft tall
- Drought tolerance: Medium
Minnesota Has
- USDA Zones: 3a-5a
- Last Hard Freeze (28°F): Apr 19 - Apr 30
- First Hard Freeze (28°F): Oct 10 - Oct 17
- Annual Rainfall: 19-34 inches
- Common Soils: Prairie loam, Clay, Sandy outwash
Plant Zone Range (zones 5-9)
Preferred Soil pH
Plant data: Growable Ground Plant Database, compiled from FAO ECOCROP, USDA PLANTS, and university Extension sources — per-field provenance varies and is published with the dataset. State data: USDA ARS PHZM 2023, NOAA Climate Normals, NRCS SSURGO.
When to Plant Willow Oak in Minnesota
The frost window
Across Minnesota, the last spring hard freeze (28°F) clears between Apr 19 and Apr 30, and the first fall hard freeze lands between Oct 10 and Oct 17 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 163-day window you can count on — up to 181 days on a mild site in a kind year. That marks the hard freeze, not the last light frost, so tender transplants usually wait another 2-3 weeks.
Winter standing
Minnesota runs as cold as USDA zone 3, and no sourced winter-hardiness floor is on record for willow oak, so this page does not state whether it overwinters here — and gives no fall establishment date on the strength of a guess. Whether willow oak is a permanent planting or a replant-every-spring crop for you turns on your own zone within Minnesota; check its hardiness range against that before treating it as long-lived ground.
Frost window: NOAA Climate Normals 1991-2020. Plant timing fields: Growable Ground Plant Database — frost-free days from FAO ECOCROP, days to harvest from university Extension production guides, and growing-degree-day and chill-hour minimums that are compilation estimates rather than published figures. Your site's own frost dates can run earlier or later than the state range — a parcel report pins them down.
Growing Season Fit
The zone check says willow oak survives winter in part of Minnesota, not across all of it. Whether the season is long enough — and warm enough — is a different question.
Chill hours
Willow Oak requires ~400 chill hours (32-45°F dormancy window). Minnesota typically banks ~2500 chill hours per winter (from PRISM 1991-2020 climate normals), which keeps this plant on track.
GDD and chill-hour figures are computed from PRISM 1991-2020 monthly climate normals; frost-free days from NOAA Regional Climate Centers ACIS, 1991-2020. Each is the state median across its counties (P25/P75 span the within-state spread). Hardiness-zone range is USDA PHZM 2023.
Soil + Drainage Fit
Willow Oak likes near-neutral soil (pH 5-7). That's the common-ground band across Minnesota's prairie loam and clay — a soil test confirms it for your site. It will grow across that whole span, but it does best between pH 5.5 and 6.5 — worth knowing before you decide whether a Minnesota soil test result is a problem or just a number. Drainage matters: this plant wants well (dry spells). If your Minnesota site is heavier clay or sits in a low spot, raised beds or amendment with compost solve it.
Plant pH requirements: FAO ECOCROP and USDA PLANTS, with the remaining rows from other published sources or Growable Ground compilation. Drainage: FAO ECOCROP, with the remaining rows from other published sources or Growable Ground compilation. Minnesota soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.
What Else to Consider for Willow Oak in Minnesota
Zone compatibility tells you about winter cold survival — but Minnesota growers also need to think about:
Extreme cold (zone 3a: -40F) limits many species
Short growing season (100-140 frost-free days)
Heavy clay soils in the Red River Valley
What to actually do about these — and the constraints that apply to every Minnesota grower, not just willow oak — is covered on the Minnesota growing guide.
Where in Minnesota Willow Oak Is Zone-Hardy
Willow Oak is rated for USDA zones 5–9. 18 of Minnesota’s 87 counties fall inside that band. The coldest that does is Blue Earth County at zone 5a. 69 counties sit below the plant’s zone 5 floor, where an unprotected plant is relying on snow cover and a mild year. Where you are in Minnesota decides this one.
Across those 87 counties Minnesota’s winter-low ladder runs from zone 3b in Beltrami County to zone 5a in Watonwan County — 1.5 USDA zones of spread, which is 15°F between the two counties’ average coldest night of the year. That is why a statewide hardiness answer is where you start and not where you finish.
The planting window moves with it. Lake County holds its last hard freeze (28°F) until about May 14, while Ramsey County is clear by Apr 10 — 34 days apart. Set willow oak out on your county’s date, not the state’s.
County hardiness zones: USDA Plant Hardiness Zone Map (PHZM) 2023, per county. County last-freeze dates: NOAA Regional Climate Centers ACIS (1991-2020), county 28°F killing freeze — earlier than the folk 32°F "last frost". Willow Oak’s zone 5–9 band: USDA PLANTS / Growable Ground plant database. A parcel report resolves your address’s own zone and frost dates rather than its county’s.
Minnesota Cooperative Extension
For Minnesota-specific cultivar recommendations, planting calendars, and pest pressure for willow oak, the canonical source is University of Minnesota Extension. Their fact sheets carry the local trial data we can't generalize across 50 states.
Is Willow Oak native to Minnesota?
Willow Oak is native to parts of the Lower 48, but the USDA PLANTS Database (accessed 2026-07-01) does not document a native range in Minnesota. It can still earn a place in a Minnesota garden — the zone comparison above tells you whether it will thrive.
Looking for plants that belong here? The Minnesota growing guide lists USDA-documented natives for the state.
Native-range data: USDA PLANTS Database state-distribution records, accessed 2026-07-01.
Common Questions About Growing Willow Oak in Minnesota
When can I plant Willow Oak in Minnesota?
Minnesota's last spring hard freeze (28°F) clears between Apr 19 and Apr 30, and the first fall hard freeze lands between Oct 10 and Oct 17 (NOAA Regional Climate Centers ACIS, 1991-2020). No sourced winter-hardiness floor is on record for Willow Oak, so this page does not state whether it overwinters in Minnesota and publishes no fall establishment date for it — check its hardiness range against your own zone before treating it as a permanent planting.
What hardiness zone is Willow Oak grown in across Minnesota?
Minnesota spans USDA hardiness zones 3a-5a (USDA ARS PHZM 2023). Willow Oak carries a range of zones 5-9, so the overlap zones are where outdoor growing is most reliable.
How many frost-free days does a typical Minnesota site have?
A typical Minnesota site sees ~174 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Willow Oak should be matched against that window, so check whether your local microclimate runs above or below the state average before settling on a planting date.
Is Willow Oak native to Minnesota?
Willow Oak is native to parts of the Lower 48, but the USDA PLANTS Database (accessed 2026-07-01) does not document a native range in Minnesota. It can still earn a place in a Minnesota garden — the zone comparison above tells you whether it will thrive.
How should I amend the soil for Willow Oak in Minnesota?
Willow Oak prefers pH 5-7 and well (dry spells) drainage (FAO ECOCROP). That sits in the common-ground band across Minnesota soils — a 30-minute soil test from a local Extension lab confirms it for your specific site.
Will Willow Oak actually grow on my specific land in Minnesota?
State-level zone + climate data is a sketch. A Growable Ground parcel report scores willow oak against your address's exact soil pH, drainage, sun, and frost-date data drawn from USDA SSURGO, NOAA, and PRISM — not state averages.
Check your specific parcel in Minnesota
State-level data is a sketch. Your Growable Ground report scores willow oak against your parcel's exact soil, sun, drainage, and frost data — not zone averages.
Three things about your lot that Minnesota willow oak averages can't show:
We read public map data around Minnesota — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Minnesota willow oak average
Explore More
Growing guides for willow oak
Explore Minnesota county by county
Minnesota carries 87 counties with their own USDA zone — a sample of the growing pages for willow oak there:
Where else willow oak grows
Willow Oak's zone band crosses state lines — these are the states closest to Minnesota in winter climate where it also has a page, plus the far ends of its range. Each one re-answers the question with that state's own record.
More to grow in Minnesota
Minnesota has a growing page for 747 plants — a rotating sample of the rest of the shelf.
Last updated: