Generally — Most Areas
black-eyed Susan (zones 3-7) suits most of Oklahoma (6b-8b) — zones 6-7 are in range, and the rest of the state is the exception.
Black Eyed Susan in Oklahoma — the short answer
Black Eyed Susan in Oklahoma: hardy in zones 3–7, full sun, against a state median of ~237 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
- Oklahoma zones
- 6b-8b
- USDA PHZM 2023
- Frost window
- Mar 15 - Mar 26 – Nov 9 - Nov 14
- NOAA RCC ACIS 1991-2020, 28°F
- Shortest county season
- 197 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.
Your yard isn't the whole zone.
Oklahoma spans zones 6b-8b, 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.
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Oklahoma is not one climate
A single Oklahoma answer averages 77 counties whose growing seasons are 70 days apart — from 197 frost-free days in Cimarron County to 267 in Choctaw County. Which end of that your land sits nearer changes what black eyed susan can finish before the first hard freeze.
The middle half of 77 counties runs 229–244 days, with a median of 237 days — a 70-day span end to end.
Measured across 77 Oklahoma 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 Oklahoma Fits Best
Black Eyed Susan is rated for zones 3–7 — a cold floor USDA puts at -40 to -30°F. Against Oklahoma’s 77 counties that band holds in 27 of them, and the line runs at Beaver County (zone 6b), the coldest county still inside it.
Inside zones 3–7
27 counties
- Cimarron County · zone 6b
- Texas County · zone 6b
- Adair County · zone 7a
3 of 27 shown
Above the zone 7 ceiling
50 counties
- Blaine County · zone 7b
- Caddo County · zone 7b
- Canadian County · zone 7b
3 of 50 shown
Too little winter chill rather than too much cold — a low-chill selection is what changes it.
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 Oklahoma's zones 6b-8b, 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
Oklahoma Has
- USDA Zones: 6b-8b
- Last Hard Freeze (28°F): Mar 15 - Mar 26
- First Hard Freeze (28°F): Nov 9 - Nov 14
- Annual Rainfall: 15-56 inches
- Common Soils: Red clay, Sandy loam, Prairie loam
Plant Zone Range (zones 3-7)
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 Black Eyed Susan in Oklahoma
The frost window
Across Oklahoma, the last spring hard freeze (28°F) clears between Mar 15 and Mar 26, and the first fall hard freeze lands between Nov 9 and Nov 14 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 228-day window you can count on — up to 244 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 Oklahoma's late-side last freeze of Mar 26 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 108 days to spare even in Oklahoma's tightest freeze scenario — room for a later start or a second sowing.
Timing tuned to sub-state frost dates — Cimarron County, not the statewide average.
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 in part of Oklahoma, not across all of it. 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 Oklahoma site has ~237 frost-free days, so plenty of room for a second succession.
Growing degree days
Black Eyed Susan needs ~1000 GDD (base 50°F) to ripen. The state median runs ~4695 GDD (from PRISM 1991-2020 climate normals), so Oklahoma'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 Oklahoma's red clay and sandy 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 Oklahoma soil test result is a problem or just a number. Drainage matters: this plant wants well (dry spells). If your Oklahoma site is heavier clay or sits in a low spot, raised beds or amendment with compost solve it.
Your land, not the state average
Oklahoma's soils run mostly silt loam, but SSURGO maps the series, texture, and drainage under your exact parcel. Black Eyed Susan needs about 19 inches of workable depth, so it is that horizon — not the surface — you are testing for. That map unit, not the state average, decides how black eyed susan performs.
Check your parcel → Source: USDA NRCS SSURGO.
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. Oklahoma 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 Oklahoma
Zone compatibility tells you about winter cold survival — but Oklahoma growers also need to think about:
Extreme weather variability (tornadoes, ice storms, drought)
Red clay soils drain poorly in central OK
Low western rainfall requires irrigation
Growing black eyed susan here specifically
Black Eyed Susan sends medium roots and rates to zones 3–7, but much of Oklahoma sits on slow-draining, restrictive ground (SSURGO hydrologic group D) that forks and stunts them.
Loosen a deep, stone-free bed for black eyed susan and break any compacted or hardpan layer before planting. How to handle it →
What to actually do about these — and the constraints that apply to every Oklahoma grower, not just black eyed susan — is covered on the Oklahoma growing guide.
Timing shifts within Oklahoma
Oklahoma isn't one climate. In Cimarron County, the last hard freeze (28°F) holds until about Apr 13 — roughly 24 days later than the recorded state median — so plant black eyed susan to your county's window, not the statewide date.
Black Eyed Susan needs about 120 days of frost-free season from planting to harvest. Even Cimarron County — Oklahoma’s shortest season at 197 frost-free days — clears that by 77 days, so season length isn’t the constraint anywhere in Oklahoma. What varies is your own parcel.
Across Oklahoma’s 77 counties the frost-free season runs from 197 days in Cimarron County to 267 days in Choctaw County — a spread of 70 days, which is why a single statewide planting date misleads. The median Oklahoma county sees 237 frost-free days, leaving black eyed susan about 117 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 Oklahoma's frost window — roughly 237 days, opening after the last 28°F freeze (Mar 15 - Mar 26) and closing at the first (Nov 9 - Nov 14), per NOAA Regional Climate Centers ACIS, 1991-2020.
Recommended Black Eyed Susan Varieties for Oklahoma
Oklahoma publishes no state variety trial for black eyed susan, so we won't invent a "best for Oklahoma" list. Choose types rated to your USDA hardiness zone (6b-8b), and confirm winter survival and drainage against your own parcel.
Oklahoma Cooperative Extension
For Oklahoma-specific cultivar recommendations, planting calendars, and pest pressure for black eyed susan, the canonical source is Oklahoma State University Extension. Their fact sheets carry the local trial data we can't generalize across 50 states.
Is Black Eyed Susan native to Oklahoma?
Yes — the USDA PLANTS Database (accessed 2026-07-01) documents Black Eyed Susan as native to Oklahoma. 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 Oklahoma
When can I plant Black Eyed Susan in Oklahoma?
Oklahoma's last spring hard freeze (28°F) clears between Mar 15 and Mar 26, and the first fall hard freeze lands between Nov 9 and Nov 14 (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 Oklahoma?
Yes — Black Eyed Susan matures in 120 days (Growable Ground Plant Database), and Oklahoma's dependable hard-freeze-free window runs 228 days (NOAA Regional Climate Centers ACIS, 1991-2020), leaving 108 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 Oklahoma?
Oklahoma spans USDA hardiness zones 6b-8b (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 Oklahoma site have?
A typical Oklahoma site sees ~237 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. In cooler counties like Cimarron, the freeze-free season runs shorter than the state average, so verify your own county's window.
Is Black Eyed Susan native to Oklahoma?
Yes — the USDA PLANTS Database (accessed 2026-07-01) documents Black Eyed Susan as native to Oklahoma. Planting it supports the pollinators and wildlife that evolved alongside it.
How should I amend the soil for Black Eyed Susan in Oklahoma?
Black Eyed Susan prefers pH 5.5-8 and well (dry spells) drainage (FAO ECOCROP). That sits in the common-ground band across Oklahoma 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 Oklahoma?
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.
Check your specific parcel in Oklahoma
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 Oklahoma black eyed susan averages can't show:
We read public map data around Oklahoma — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Oklahoma black eyed susan average
Explore More
Growing guides for black eyed susan
Explore Oklahoma county by county
Oklahoma carries 77 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 Oklahoma 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 Oklahoma
Oklahoma has a growing page for 1,020 plants — a rotating sample of the rest of the shelf.
Analysis by the Growable Ground research team, grounded in USDA PLANTS, USDA NRCS SSURGO, NOAA Climate Normals (1991-2020), and named Cooperative Extension sources. How we know →
Cite this dataset
Kirchick, M. (2026). Growable Ground Plant Database [Data set]. Zenodo. https://doi.org/10.5281/zenodo.21435643
Licensed CC BY-NC 4.0. DOI 10.5281/zenodo.21435643
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