Optima, Oklahoma, sits in USDA hardiness zone 6b — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
A short list that earns its place here — cabbage, hazelnut, lavender, and collard greens — with any one site's soil, sun, and drainage making the final cut.
Even in Optima, 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 Optima lot. Enter your address and we'll score 1,086 plants against your land's actual soil, sun, and frost.
We read public map data around Optima — soil, climate, flood, and parcel records. How we handle your address.
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Optima — the short answer
Optima, Oklahoma: USDA zone 6b, about 202 days between hard freezes, across 341 acres of town.
- USDA zone
- 6b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 10
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 29
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~202
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 341 acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. Hard-freeze dates are this town’s own 28°F normals: light frosts run a few weeks past them, and tender transplants usually wait 2–3 weeks after the last hard freeze.
Hardiness Zone Range
Zone 6b is Optima's average, not your lot's — a low corner or a tree line moves it. Against Optima's 202-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Optima
Each reading below is measured for Optima itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredOptima runs about 202 days between hard freezes — a long growing season.
There is slack for succession plantings and slow-finishing crops: many vegetables can be sown twice, and the heat-lovers have time to ripen fully.
Plan a second sowing of quick crops after the first comes out, and use the fall window most gardeners let sit idle.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredOptima sits in USDA hardiness zone 6b.
The zone sets which perennials, shrubs, and fruit trees live through an average winter here — a plant rated for a colder zone is a safe bet, one rated warmer needs winter protection or gets treated as an annual.
Match perennials and fruit to the zone before you buy, so nothing you plant is a gamble against the cold.
USDA PHZM 2023
The kind of country Optima is in
Optima sits in the Southwestern Tablelands — EPA Level III, inside the wider Great Plains. That is read at Optima's own centroid, and it is not what its county reads: Texas County is mostly High Plains. The wider page above you is answering a different question about different ground.
What Grows in Optima
Every plant below cleared Optima's own zone 6b and its 202-day season. Each card opens that plant's Oklahoma profile. How we score.
Is it too late to plant in Optima?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Mar 13; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 10 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 29 — 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.
What's on the federal record near Optima
Closest first, within ~10 miles of Optima. Listing isn't leaking, and distance isn't exposure.
- J. A. Atkins, JrUnderground Storage Tanks · 2100 ft
- SB Wright FinisherNitrate · 1.5 mi
- Fac. Name: Finisher 346, Well No. 22Nitrate · 1.8 mi
- HERBEL LAND AND CATTLECAFO · 2.6 mi
- 04N-16E-19 DBB 1Nitrate · 2.8 mi
- CHAMPION FEEDERS - HITCH ICAFO · 3.0 mi
- GROUNDS FEEDERS, LLCCAFO · 3.1 mi
- SB Lindsay FinisherNitrate · 3.5 mi
- Fac. Name: Finisher 355&356, Well No. 24Nitrate · 3.5 mi
- SB Mouser II Com. Fin.Nitrate · 3.5 mi
- 04N-16E-17 CBB 1Nitrate · 3.6 mi
- 04N-16E-24 CBC 2Nitrate · 3.8 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Optima's center, not your beds. Run your own address for what's upwind of you specifically.
Environmental Intelligence
The counts behind that headline — every source type on the record near Optima.
Total Sites
203
within ~10 miles of Optima
Risk Level
Elevated
Highest-severity
3 Toxics Release Inventory facilities
Sources Checked
within ~10 miles of Optima
Severity Distribution
within ~10 miles of Optima
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Optima, two things run higher than the national average within ~10 miles of Optima — CAFO (13 sites) and Nitrate (98 sites). That's not a problem with your land — it's information about it.
CAFO: CAFOs pose a different contamination profile than chemical sources.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Wash all produce consumed raw thoroughly, especially leafy greens grown near CAFOs.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in Optima
Get exact proximity distances to contamination sources for your specific parcel — plus soil, sun, drainage, and 1,086 plant recommendations.
25+ data sources read at your address, not the Optima average
Your land is one point inside Optima
Everything above resolves to Optima as a whole — one PHZM band and one 28°F frost record, read across 341 acres. Your parcel is one point inside that footprint. Slope, tree cover, a low spot that pools cold air, and what is in the soil are all resolved at the address, and none of them are visible at town scale. That is the honest boundary of this page, and the reason the next step is a reading of your own ground rather than a better local average.
Your Lot vs the Optima Average
Optima Average
- ●USDA Zones 6b, averaged across Optima
- ●One soil character for all of Optima
- ●Frost dates read at Optima's scale: Apr 10 to Oct 29
YOUR Parcel
- ✓Your exact zone, not Optima's 6b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Optima
Pull a site-specific report for your exact address in Optima, Oklahoma — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Optima averages can't show:
We read public map data around Optima — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Optima average
How we know this about Optima
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this town’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Optima’s own record; boundaries and acreage from US Census TIGER/Line 2025; the contamination records from the federal sources named in their beats above. Soil is not read at town grain anywhere on this page — there is no town-resolution survey in our data, which is why you will find no soil grid here rather than a statewide one wearing a local label. The resolution ledger below names every figure this page inherited.
Common questions about Optima
When does frost risk typically end in Optima?
The last hard freeze (28°F) in Optima typically lands around Apr 10, per NOAA 1991–2020 climate normals — earlier than the light-frost dates most charts quote. That marks the hard freeze, not the last light frost — lighter frosts keep biting past it, which is why tender transplants here wait until about May 1.
When is the first frost in Optima?
The first hard freeze (28°F) in Optima typically arrives around Oct 29, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 15, so the watching starts about Sep 29 — about 202 days after the spring freeze cleared.
How long is the growing season in Optima?
Measured between 28°F hard freezes, Optima sees about 202 frost-free days — roughly Apr 10 through Oct 29, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 1 to Oct 15, about 167 days.
Is the soil safe to grow vegetables in Optima?
The federal record around Optima is a meaningful one — 203 documented sites, mostly Nitrate entries (98), the nearest Underground Storage Tanks record about 0.4 miles out — 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 Optima?
From about Sep 29 the job here turns from planting to protecting — the last start even a 30-day crop can finish. As the season closes around the first 28°F hard freeze near Oct 29 (NOAA 1991–2020 climate normals), three moves buy time: row cover or an old sheet over tender plants on still, clear nights; water the soil the afternoon before a freeze, so it holds warmth overnight; and harvest tomatoes, peppers and basil before Oct 29. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Optima's scale — its 6b band and its 202-day season. Your yard writes its own version of Optima's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
What this page reads at Optima’s own scale
6 of the readings below were taken at Optima's own scale — its own ~202-day season between 28°F freezes, the 341 acres it covers and 203 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Optima's own USDA hardiness band, zones 6bUSDA PHZM 2023
- Optima's own 28°F hard-freeze dates, about Apr 10 and Oct 29 and the ~202-day span between themNOAA 1991–2020 Climate Normals
- 203 documented contamination sites on the federal record near Optima, the closest Underground Storage Tanks record about 0.4 miles out from the town centreFederal environmental registers
- Optima's boundary and the 341 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6b and a ~202-day seasonGrowable Ground crop-matching engine
- Optima sits in the Southwestern Tablelands — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Optima's 341 acres read through its county's SSURGO summaryfrom Texas County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Texas County
- The growing challenges every Oklahoma grower plans around — written at state scale, so they stay on the state guidefrom Oklahoma
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Texas County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Optima's 341 acreswhy one lot differs from the next →
- Which side of Optima you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 341 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.4 miles out, measured from the town centrehow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — measured at your address, and averaged away by any Optima-wide figureread your own land →
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