she oak (Casuarina equisetifolia), photographi

Can I Grow She Oak in Kentucky?

USDA Zones 6a-7b · Plant zone range 9-12

Unlikely — Zone Mismatch

she oak (zones 9-12) does not overlap with Kentucky's zone range (6a-7b). Growing outdoors is unlikely without significant protection.

2 zones short — what would close it

She Oak is hardy to zone 9, and the warmest ground in Kentucky is zone 7 — 2 zones short. Planted in open ground it will not survive a Kentucky winter. To grow it here, grow she oak in an earth-sheltered greenhouse — its modeled 2.5-zone lift covers this gap.

An earth-sheltered greenhouse is the lift this needs. How a greenhouse changes what you can grow →

Zone math from 9-12 (plant) against 6-7 (Kentucky). Lift modeled by crop_engine.GREENHOUSE_ZONE_MODIFIER_BY_SUBTYPE['earth_sheltered'] (+2.5 zones) via api/fast_sections.py Unlock Engine v2.

She Oak in Kentucky — the short answer

She Oak in Kentucky: hardy in zones 9–12, full sun, against a state median of ~221 frost-free days.

Plant zones
9-12
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
Kentucky zones
6a-7b
USDA PHZM 2023
Frost window
Mar 27 - Apr 2 – Nov 4 - Nov 10
NOAA RCC ACIS 1991-2020, 28°F
Shortest county season
195 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.

Score your parcel · free

Your yard isn't the whole zone.

Kentucky spans zones 6a-7b, 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 she 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.

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Kentucky is not one climate

Kentucky’s winter-low ladder runs across 120 counties, from zone 6.5 in Anderson County to zone 7.5 in Lyon County. That is 10°F between the two counties’ average coldest night — the difference between she oak overwintering in the ground and coming under cover.

6.5 zonesAnderson County7.5 zonesLyon County

The middle half of 120 counties runs 6.57 zones, with a median of 7 zones — a 1-zone span end to end.

Measured across 120 Kentucky 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 She Oak Stands in Kentucky

She Oak is rated for zones 912 — a cold floor USDA puts at 20 to 30°F. No Kentucky county sits inside it, so in open ground this is a grown-under-cover plant here rather than a bed plant — which is a statement about Kentucky winters, not about she oak.

Below the zone 9 floor

120 counties

3 of 120 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.

Zone Comparison

She Oak Needs

  • USDA Zones: 9-12
  • Frost-Free Days: 100+
  • Sun: Full Sun
  • Mature size: 70 ft tall
  • Drought tolerance: Low

Kentucky Has

  • USDA Zones: 6a-7b
  • Last Hard Freeze (28°F): Mar 27 - Apr 2
  • First Hard Freeze (28°F): Nov 4 - Nov 10
  • Annual Rainfall: 42-52 inches
  • Common Soils: Silt loam, Clay loam, Limestone-derived

Plant Zone Range (zones 9-12)

9a
12b
3a (Cold)13b (Hot)

Preferred Soil pH

3.5 (Acidic)7.0 (Neutral)9.0 (Alkaline)
Highlighted range: pH 4.08.5

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 She Oak in Kentucky

The frost window

Across Kentucky, the last spring hard freeze (28°F) clears between Mar 27 and Apr 2, and the first fall hard freeze lands between Nov 4 and Nov 10 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 216-day window you can count on — up to 228 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

Kentucky runs as cold as USDA zone 6, and no sourced winter-hardiness floor is on record for she oak, so this page does not state whether it overwinters here — and gives no fall establishment date on the strength of a guess. Whether she oak is a permanent planting or a replant-every-spring crop for you turns on your own zone within Kentucky; check its hardiness range against that before treating it as long-lived ground.

Timing tuned to sub-state frost dates — Greenup 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 she oak does not survive a Kentucky winter in the ground. The season figures below measure a different question — whether it could finish a season here at all — and they only bear on Kentucky under protection.

Frost-free days

She Oak wants 100+ frost-free days; a typical Kentucky site sees ~221 (NOAA Regional Climate Centers ACIS, 1991-2020). That leaves comfortable headroom for succession planting.

Chill hours

She Oak has no winter-chill requirement — its listed minimum is 0 hours (Growable Ground Plant Database). Kentucky typically banks ~2500 chill hours per winter (from PRISM 1991-2020 climate normals), so chill is not a constraint on this plant here — and not evidence in its favour either. Winter survival and season length are what decide it.

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

She Oak tolerates a wide pH range (pH 4-8.5) — 4.5 units, acid ground through alkaline — so soil acidity is rarely what limits it in Kentucky. A soil test is still worth having, but for what else it tells you about this site, not to clear this plant. It will grow across that whole span, but it does best between pH 5 and 6.5 — worth knowing before you decide whether a Kentucky soil test result is a problem or just a number. Drainage matters: this plant wants poorly (saturated >50% of year), well (dry spells). If your Kentucky site is heavier clay or sits in a low spot, raised beds or amendment with compost solve it.

Your land, not the state average

Kentucky's soils run mostly silt loam, but SSURGO maps the series, texture, and drainage under your exact parcel. She Oak needs about 59 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 she oak 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. Kentucky soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.

What Else to Consider for She Oak in Kentucky

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

Heavy clay soils in the Bluegrass region

High humidity promotes fungal diseases

Karst topography creates drainage unpredictability

Growing she oak here specifically

She Oak needs pH 4.0–8.5; Kentucky's dominant silt loam soils may or may not deliver that, so your parcel's SSURGO map unit is the real test.

Start with a soil test on your own ground and adjust pH and texture to fit she oak's 4.0–8.5 range. How to handle it →

What to actually do about these — and the constraints that apply to every Kentucky grower, not just she oak — is covered on the Kentucky growing guide.

Timing shifts within Kentucky

Kentucky isn't one climate. In Greenup County, the last hard freeze (28°F) holds until about Apr 13 — roughly 13 days later than the recorded state median — so plant she oak to your county's window, not the statewide date.

She Oak needs about 100 days of frost-free season to complete its cycle. Even Greenup County — Kentucky’s shortest season at 195 frost-free days — clears that by 95 days, so season length isn’t the constraint anywhere in Kentucky. What varies is your own parcel.

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"). She Oak's 100-day requirement: USDA PLANTS / Growable Ground plant database (minimum frost-free days). A parcel report resolves your address's own frost dates.

Kentucky Cooperative Extension

For Kentucky-specific cultivar recommendations, planting calendars, and pest pressure for she oak, the canonical source is University of Kentucky Cooperative Extension. Their fact sheets carry the local trial data we can't generalize across 50 states.

Is She Oak native to Kentucky?

No — the USDA PLANTS Database lists She Oak as introduced rather than native in the Lower 48, so it is not part of Kentucky's native flora. It grows here as a garden plant; pairing it with a few Kentucky natives keeps local pollinators fed too.

Looking for plants that belong here? The Kentucky 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 She Oak in Kentucky

When can I plant She Oak in Kentucky?

Kentucky's last spring hard freeze (28°F) clears between Mar 27 and Apr 2, and the first fall hard freeze lands between Nov 4 and Nov 10 (NOAA Regional Climate Centers ACIS, 1991-2020). No sourced winter-hardiness floor is on record for She Oak, so this page does not state whether it overwinters in Kentucky 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 She Oak grown in across Kentucky?

Kentucky spans USDA hardiness zones 6a-7b (USDA ARS PHZM 2023). She Oak carries a range of zones 9-12, so the overlap zones are where outdoor growing is most reliable.

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

A typical Kentucky site sees ~221 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). She Oak needs 100+ frost-free days, so check whether your local microclimate runs above or below the state average before settling on a planting date. In cooler counties like Greenup, the freeze-free season runs shorter than the state average, so verify your own county's window.

Is She Oak native to Kentucky?

No — the USDA PLANTS Database lists She Oak as introduced rather than native in the Lower 48, so it is not part of Kentucky's native flora. It grows here as a garden plant; pairing it with a few Kentucky natives keeps local pollinators fed too.

How should I amend the soil for She Oak in Kentucky?

She Oak tolerates pH 4-8.5 and poorly (saturated >50% of year), well (dry spells) drainage (FAO ECOCROP). That is a 4.5-unit span, acid ground through alkaline, so pH is rarely what limits this plant on a Kentucky site — amend for drainage and organic matter first.

Will She Oak actually grow on my specific land in Kentucky?

State-level zone + climate data is a sketch. A Growable Ground parcel report scores she oak 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 Kentucky

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

Three things about your lot that Kentucky she oak averages can't show:

Your soil pHYour frost-free days — Kentucky averages 221Your sun & shade

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

25+ data sources read at your address, not the Kentucky she oak average

Explore More

Explore Kentucky county by county

Kentucky carries 120 counties with their own USDA zone — a sample of the growing pages for she oak there:

Where else she oak grows

She Oak's zone band crosses state lines — these are the states closest to Kentucky 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 Kentucky

Kentucky has a growing page for 893 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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