Yes — Strong Match
purple basil is grown as an annual, so season length decides it here, not a winter zone — and Arizona's typical season runs ~266 frost-free days against the ~80 purple basil needs.
Purple Basil in Arizona — the short answer
Purple Basil in Arizona: grown in zones 10–11, full sun, against a state median of ~266 frost-free days.
- Plant zones
- 10-11
- Not verified
- Arizona zones
- 5b-10b
- USDA PHZM 2023
- Frost window
- Feb 1 - Apr 2 – Nov 13 - Dec 12
- NOAA RCC ACIS 1991-2020, 28°F
- Shortest county season
- 150 days
- NOAA Regional Climate Centers ACIS, 1991-2020, county 28°F killing freeze
- Days to maturity
- 70 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.
Arizona spans zones 5b-10b, 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 purple basil 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 parcel report in seconds — read in full free for your first 14 days
Arizona is not one climate
A single Arizona answer averages 15 counties whose growing seasons are 195 days apart — from 150 frost-free days in Coconino County to 345 in Maricopa County. Which end of that your land sits nearer changes what purple basil can finish before the first hard freeze.
The middle half of 15 counties runs 207–316 days, with a median of 266 days — a 195-day span end to end.
Measured across 15 Arizona 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.
Zone Comparison
Purple Basil Needs
- USDA Zones: 10-11
- Frost-Free Days: 80+
- Sun: Full SunWe haven't confirmed this against a published source yet.
- Mature size: 1.5 ft tallWe haven't confirmed this against a published source yet.
- Picking window: ~90 days of harvestWe haven't confirmed this against a published source yet.
- Drought tolerance: LowWe haven't confirmed this against a published source yet.
Arizona Has
- USDA Zones: 5b-10b
- Last Hard Freeze (28°F): Feb 1 - Apr 2
- First Hard Freeze (28°F): Nov 13 - Dec 12
- Annual Rainfall: 3-25 inches
- Common Soils: Caliche, Sandy loam, Desert pavement
Plant Zone Range (zones 10-11)
Preferred Soil pH
We haven't confirmed this against a published source yet.
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 Purple Basil in Arizona
The frost window
Across Arizona, the last spring hard freeze (28°F) clears between Feb 1 and Apr 2, and the first fall hard freeze lands between Nov 13 and Dec 12 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 225-day window you can count on — up to 314 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.
When to start the seed
Those dates are when purple basil goes out, not when it starts. It is sown under cover about 6 weeks ahead, so counting back from Arizona's late-side last freeze of Apr 2 is what fixes your sowing date — and a yard that clears frost earlier than the state's late date starts earlier still.
Winter standing
Arizona runs as cold as USDA zone 5, and no sourced winter-hardiness floor is on record for purple basil, so this page does not state whether it overwinters here — and gives no fall establishment date on the strength of a guess. Whether purple basil is a permanent planting or a replant-every-spring crop for you turns on your own zone within Arizona; 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
Frost-free days
Purple Basil wants 80+ frost-free days; a typical Arizona site sees ~266 (NOAA Regional Climate Centers ACIS, 1991-2020). That leaves comfortable headroom for succession planting.
Growing degree days
Purple Basil needs ~1500 GDD (base 50°F) to ripen. We haven't confirmed this against a published source yet. The state median runs ~3945 GDD (from PRISM 1991-2020 climate normals), so Arizona'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
Purple Basil tolerates a wide pH range (pH 4.3-8.2) — 3.9 units, acid ground through alkaline — so soil acidity is rarely what limits it in Arizona. 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 6 and 7 — worth knowing before you decide whether a Arizona soil test result is a problem or just a number. Drainage matters: this plant wants well (dry spells). If your Arizona site is heavier clay or sits in a low spot, a raised bed lifts the roots above wet ground, or work in compost. pH range, preferred pH and drainage need: We haven't confirmed this against a published source yet.
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. Arizona soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.
Before you plant purple basil for food
Anything you grow to eat takes up what is in the ground it grows in, so what is on record near you is worth knowing before purple basil goes in. What follows is Arizona’s documented federal record at state scale — a screening signal, not a soil test, and not a statement about any one lot.
Safe to Grow Here?
What the federal record shows across Arizona — and how to grow with it.
We checked the federal record across Arizona — 18,099 documented sites across 6 of the 8 source types we track.
The most significant on record: 184 Superfund sites. Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.
Arizona carries one of the heavier federal records we track — and that's not a verdict on your yard. Proximity to a documented site is information, not a diagnosis: nothing here says any particular parcel is affected. It does earn one concrete step — before food beds go in the ground, a professional soil test tells you exactly what you're working with, and raised beds of imported, lab-tested soil grow well almost anywhere in the meantime.
Sources Checked
across Arizona
Severity Distribution
across Arizona
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Arizona, Mining runs higher than the national average — 6,160 sites across Arizona. Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
Mining: Mining sites — both historic and active — can leach heavy metals (arsenic, lead, cadmium, mercury) into soil and water for centuries after operations cease.
Test soil for heavy metals (lead, arsenic, cadmium, mercury) — this is essential near any mining site.
Sources: EPA, USGS — 950K documented sites tracked nationwide across 8 federal source types.
What Else to Consider for Purple Basil in Arizona
The zone range tells you where purple basil is grown — but Arizona growers also need to think about:
Extreme heat exceeding 110F stresses most plants
Minimal rainfall requires drip irrigation
Caliche hardpan prevents root penetration without breaking through
What to actually do about these — and the constraints that apply to every Arizona grower, not just purple basil — is covered on the Arizona growing guide.
Timing shifts within Arizona
Purple Basil needs about 80 days of frost-free season to complete its cycle. Even Coconino County — Arizona’s shortest season at 150 frost-free days — clears that by 70 days, so season length isn’t the constraint anywhere in Arizona. What varies is your own parcel.
Across Arizona’s 15 counties the frost-free season runs from 150 days in Coconino County to 345 days in Maricopa County — a spread of 195 days, which is why a single statewide planting date misleads. The median Arizona county sees 266 frost-free days, leaving purple basil about 186 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"). Purple Basil's 80-day requirement: USDA PLANTS / Growable Ground plant database (minimum frost-free days). A parcel report resolves your address's own frost dates.
Pollinator + Wildlife Value
Purple Basil draws honeybees and native bees (moderate value). Planting it near vegetable beds can lift fruit set on neighboring crops. Outdoors, purple basil can only work that bloom inside Arizona's frost window — roughly 266 days, opening after the last 28°F freeze (Feb 1 - Apr 2) and closing at the first (Nov 13 - Dec 12), per NOAA Regional Climate Centers ACIS, 1991-2020. Pollinator value: We haven't confirmed this against a published source yet.
Good to Know Before You Plant Purple Basil
Listed as non-toxic to dogs and cats by a source we can't cite. We haven't confirmed this against a published source yet.
Arizona Cooperative Extension
For Arizona-specific cultivar recommendations, planting calendars, and pest pressure for purple basil, the canonical source is University of Arizona Cooperative Extension. Their fact sheets carry the local trial data we can't generalize across 50 states.
Is Purple Basil native to Arizona?
No — the USDA PLANTS Database lists Purple Basil as introduced rather than native in the Lower 48, so it is not part of Arizona's native flora. It grows here as a garden plant; pairing it with a few Arizona natives keeps local pollinators fed too.
Looking for plants that belong here? The Arizona growing guide lists plants that USDA PLANTS records growing in Arizona and that Kew and NatureServe Explorer both list in its native range, leaving out any that NatureServe flags as exotic there or that our audit holds.
State records: USDA PLANTS Database state-distribution data (presence, not state-level nativity), accessed 2026-10-19.
Common Questions About Growing Purple Basil in Arizona
When can I plant Purple Basil in Arizona?
Arizona's last spring hard freeze (28°F) clears between Feb 1 and Apr 2, and the first fall hard freeze lands between Nov 13 and Dec 12 (NOAA Regional Climate Centers ACIS, 1991-2020). No sourced winter-hardiness floor is on record for Purple Basil, so this page does not state whether it overwinters in Arizona 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 Purple Basil grown in across Arizona?
Arizona spans USDA hardiness zones 5b-10b (USDA ARS PHZM 2023). Purple Basil carries a range of zones 10-11, so the overlap zones are where outdoor growing is most reliable.
How many frost-free days does a typical Arizona site have?
A typical Arizona site sees ~266 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Purple Basil needs 80+ frost-free days, so check whether your local microclimate runs above or below the state average before settling on a planting date.
Is Purple Basil native to Arizona?
No — the USDA PLANTS Database lists Purple Basil as introduced rather than native in the Lower 48, so it is not part of Arizona's native flora. It grows here as a garden plant; pairing it with a few Arizona natives keeps local pollinators fed too.
How should I amend the soil for Purple Basil in Arizona?
Purple Basil tolerates pH 4.3-8.2 and well (dry spells) drainage. We haven't confirmed this against a published source yet. That is a 3.9-unit span, acid ground through alkaline, so pH is rarely what limits this plant on a Arizona site — amend for drainage and organic matter first.
Will Purple Basil actually grow on my specific land in Arizona?
State-level zone + climate data is a sketch. A Growable Ground parcel report scores purple basil against your address's mapped soil pH, drainage, sun, and frost-date data drawn from USDA SSURGO, NOAA, and PRISM — not state averages.
Check your specific parcel in Arizona
State-level data is a sketch. Your Growable Ground report scores purple basil against your land's mapped soil, modelled sun, drainage, and frost data — not zone averages.
Three things about your lot that Arizona purple basil averages can't show:
We read public map data around Arizona — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Arizona purple basil average
Explore More
Growing guides for purple basil
Explore Arizona county by county
Arizona carries 15 counties with their own USDA zone — a sample of the growing pages for purple basil there:
Where else purple basil grows
Purple Basil's zone band crosses state lines — these are the states closest to Arizona 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 Arizona
Arizona has a growing page for 1,036 plants — a rotating sample of the rest of the shelf.
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