black-eyed Susan (Rudbeckia hirta), photographi

Can I Grow Black Eyed Susan in Wisconsin?

USDA Zones 3b-6a · Plant zone range 3-7

Yes — Strong Match

black-eyed Susan (zones 3-7) covers every zone Wisconsin contains (3b-6a), so hardiness is not what limits it anywhere in the state.

Black Eyed Susan in Wisconsin — the short answer

Black Eyed Susan in Wisconsin: hardy in zones 3–7, full sun, against a state median of ~173 frost-free days.

Plant zones
3-7
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
Wisconsin zones
3b-6a
USDA PHZM 2023
Frost window
Apr 17 - May 2 – Oct 9 - Oct 21
NOAA RCC ACIS 1991-2020, 28°F
Shortest county season
140 days
NOAA Regional Climate Centers ACIS, 1991-2020, county 28°F killing freeze
Days to maturity
120 days
Growable Ground Plant Database

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.

Score your parcel · free

Your yard isn't the whole zone.

Wisconsin spans zones 3b-6a, but your yard has its own microclimate — slope, trees, and low spots shift frost and sun across a single parcel. Enter your address and we'll score black eyed susan 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.

No card required · your full report in seconds

Wisconsin is not one climate

A single Wisconsin answer averages 72 counties whose growing seasons are 77 days apart — from 140 frost-free days in Florence County to 217 in Milwaukee County. Which end of that your land sits nearer changes what black eyed susan can finish before the first hard freeze.

140 daysFlorence County217 daysMilwaukee County

The middle half of 72 counties runs 158187 days, with a median of 173 days — a 77-day span end to end.

Measured across 72 Wisconsin counties. NOAA Regional Climate Centers ACIS, 1991-2020, county 28°F killing freeze. 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 Wisconsin Fits Best

Even within Wisconsin's zones 3b-6a, county microclimates differ enough to change what thrives. These counties carry the closest zone match for black eyed susan (USDA PHZM 2023):

Zone Comparison

Black Eyed Susan Needs

  • USDA Zones: 3-7
  • Sun: Full Sun
  • Mature size: 1 ft tall
  • Picking window: ~45 days of harvest
  • Drought tolerance: Medium

Wisconsin Has

  • USDA Zones: 3b-6a
  • Last Hard Freeze (28°F): Apr 17 - May 2
  • First Hard Freeze (28°F): Oct 9 - Oct 21
  • Annual Rainfall: 28-34 inches
  • Common Soils: Silt loam, Clay loam, Sandy outwash

Plant Zone Range (zones 3-7)

3a
7b
3a (Cold)13b (Hot)

Preferred Soil pH

3.5 (Acidic)7.0 (Neutral)9.0 (Alkaline)
Highlighted range: pH 5.58.0

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 Black Eyed Susan in Wisconsin

The frost window

Across Wisconsin, the last spring hard freeze (28°F) clears between Apr 17 and May 2, and the first fall hard freeze lands between Oct 9 and Oct 21 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 160-day window you can count on — up to 187 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.

Frost tenderness

Black Eyed Susan is frost-tender — FAO ECOCROP puts its killing temperature at 32°F — so set plants out two to three weeks PAST your local last hard freeze, not on it and not on the state's earliest date. The 28°F marker above is when killing freezes stop, not when light frost does. That is the point where cold damages growing tissue, not a winter-survival floor — an established perennial comes through far colder while dormant, which is what its hardiness zone tells you.

When to start the seed

Those dates are when black eyed susan goes out, not when it starts. It is sown under cover about 8 weeks ahead, so counting back from Wisconsin's late-side last freeze of May 2 is what fixes your sowing date — and a yard that clears frost earlier than the state's late date starts earlier still.

Days to maturity vs. the window

At 120 days to maturity (Growable Ground Plant Database), counting from the last hard freeze it ripens with 40 days to spare even in Wisconsin's tightest freeze scenario — room for a later start or a second sowing.

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 black eyed susan survives winter here. Whether the season is long enough — and warm enough — is a different question.

Days to maturity

Black Eyed Susan matures in ~120 days (Growable Ground Plant Database). A typical Wisconsin site has ~173 frost-free days, so one full crop fits, with little room for replant.

Growing degree days

Black Eyed Susan needs ~1000 GDD (base 50°F) to ripen. The state median runs ~2102 GDD (from PRISM 1991-2020 climate normals), so Wisconsin's typical season clears that easily.

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

Black Eyed Susan likes near-neutral soil (pH 5.5-8). That's the common-ground band across Wisconsin's silt loam and clay loam — a soil test confirms it for your site. It will grow across that whole span, but it does best between pH 6.5 and 7.5 — worth knowing before you decide whether a Wisconsin soil test result is a problem or just a number. Drainage matters: this plant wants well (dry spells). If your Wisconsin 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. Wisconsin soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.

What Else to Consider for Black Eyed Susan in Wisconsin

Zone compatibility tells you about winter cold survival — but Wisconsin growers also need to think about:

Cold winters (-30F in northern WI)

Short growing season (110-140 frost-free days)

Sandy central soils drain too quickly

What to actually do about these — and the constraints that apply to every Wisconsin grower, not just black eyed susan — is covered on the Wisconsin growing guide.

Timing shifts within Wisconsin

Black Eyed Susan needs about 120 days of frost-free season from planting to harvest. Even Florence County — Wisconsin’s shortest season at 140 frost-free days — clears that by 20 days, so season length isn’t the constraint anywhere in Wisconsin. What varies is your own parcel.

Across Wisconsin’s 72 counties the frost-free season runs from 140 days in Florence County to 217 days in Milwaukee County — a spread of 77 days, which is why a single statewide planting date misleads. The median Wisconsin county sees 173 frost-free days, leaving black eyed susan about 53 days of slack on a typical parcel — room for a second sowing where the season runs long.

County last-freeze dates and frost-free day counts: NOAA Regional Climate Centers ACIS (1991-2020), county 28°F freeze (earlier than the folk 32°F "last frost"). Black Eyed Susan's 120-day requirement: USDA PLANTS / Growable Ground plant database (days to maturity). A parcel report resolves your address's own frost dates.

Pollinator + Wildlife Value

Black Eyed Susan draws honeybees, native bees, and butterflies (high value, Growable Ground Plant Database). Planting it near vegetable beds can lift fruit set on neighboring crops. Outdoors, black eyed susan can only work that bloom inside Wisconsin's frost window — roughly 173 days, opening after the last 28°F freeze (Apr 17 - May 2) and closing at the first (Oct 9 - Oct 21), per NOAA Regional Climate Centers ACIS, 1991-2020.

Wisconsin Cooperative Extension

For Wisconsin-specific cultivar recommendations, planting calendars, and pest pressure for black eyed susan, the canonical source is UW–Madison Division of Extension. Their fact sheets carry the local trial data we can't generalize across 50 states.

Is Black Eyed Susan native to Wisconsin?

Yes — the USDA PLANTS Database (accessed 2026-07-01) documents Black Eyed Susan as native to Wisconsin. Planting it supports the pollinators and wildlife that evolved alongside it.

Native-range data: USDA PLANTS Database state-distribution records, accessed 2026-07-01.

Common Questions About Growing Black Eyed Susan in Wisconsin

When can I plant Black Eyed Susan in Wisconsin?

Wisconsin's last spring hard freeze (28°F) clears between Apr 17 and May 2, and the first fall hard freeze lands between Oct 9 and Oct 21 (NOAA Regional Climate Centers ACIS, 1991-2020). Black Eyed Susan is frost-tender — its killing temperature is 32°F (FAO ECOCROP — the point where cold damages growing tissue, not a winter-survival floor) — so wait two to three weeks past your site's last hard freeze, when light frost has also stopped, before planting out.

Can Black Eyed Susan mature before first frost in Wisconsin?

Yes — Black Eyed Susan matures in 120 days (Growable Ground Plant Database), and Wisconsin's dependable hard-freeze-free window runs 160 days (NOAA Regional Climate Centers ACIS, 1991-2020), leaving 40 days of margin. Plant once the last hard freeze has passed — two to three weeks later for anything tender — and it ripens ahead of the first fall freeze.

What hardiness zone is Black Eyed Susan grown in across Wisconsin?

Wisconsin spans USDA hardiness zones 3b-6a (USDA ARS PHZM 2023). Black Eyed Susan carries a range of zones 3-7, so the overlap zones are where outdoor growing is most reliable.

How many frost-free days does a typical Wisconsin site have?

A typical Wisconsin site sees ~173 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Black Eyed Susan 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 Black Eyed Susan native to Wisconsin?

Yes — the USDA PLANTS Database (accessed 2026-07-01) documents Black Eyed Susan as native to Wisconsin. Planting it supports the pollinators and wildlife that evolved alongside it.

How should I amend the soil for Black Eyed Susan in Wisconsin?

Black Eyed Susan prefers pH 5.5-8 and well (dry spells) drainage (FAO ECOCROP). That sits in the common-ground band across Wisconsin soils — a 30-minute soil test from a local Extension lab confirms it for your specific site.

Will Black Eyed Susan actually grow on my specific land in Wisconsin?

State-level zone + climate data is a sketch. A Growable Ground parcel report scores black eyed susan against your address's exact soil pH, drainage, sun, and frost-date data drawn from USDA SSURGO, NOAA, and PRISM — not state averages.

Free Report

Check your specific parcel in Wisconsin

State-level data is a sketch. Your Growable Ground report scores black eyed susan against your parcel's exact soil, sun, drainage, and frost data — not zone averages.

Three things about your lot that Wisconsin black eyed susan averages can't show:

Your soil pHYour frost-free days — Wisconsin averages 173Your sun & shade

We read public map data around Wisconsin — soil, climate, flood, and parcel records. How we handle your address.

25+ data sources read at your address, not the Wisconsin black eyed susan average

Explore More

Explore Wisconsin county by county

Wisconsin carries 72 counties with their own USDA zone — a sample of the growing pages for black eyed susan there:

Where else black eyed susan grows

Black Eyed Susan's zone band crosses state lines — these are the states closest to Wisconsin 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 Wisconsin

Wisconsin has a growing page for 806 plants — a rotating sample of the rest of the shelf.

Last updated: