Conditional — Some Areas
coral tree (zones 10-12) reaches only part of Arizona (5b-10b): zone 10 are in range, so where you are in the state decides it.
Coral Tree in Arizona — the short answer
Coral Tree in Arizona: hardy in zones 10–12, full sun, against a state median of ~266 frost-free days.
- Plant zones
- 10-12
- 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
- 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
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 coral tree against your parcel's actual hardiness, soil, and sun.
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Arizona is not one climate
Arizona’s winter-low ladder runs across 15 counties, from zone 6 in Coconino County to zone 9.5 in Yuma County. That is 35°F between the two counties’ average coldest night — the difference between coral tree overwintering in the ground and coming under cover.
The middle half of 15 counties runs 7.5–9.5 zones, with a median of 8.5 zones — a 3.5-zone span end to end.
Measured across 15 Arizona 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 Coral Tree Stands in Arizona
Coral Tree is rated for zones 10–12 — a cold floor USDA puts at 30 to 40°F. No Arizona 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 Arizona winters, not about coral tree.
Below the zone 10 floor
15 counties
- Coconino County · zone 6a
- Apache County · zone 6b
- Navajo County · zone 7a
3 of 15 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
Coral Tree Needs
- USDA Zones: 10-12
- Frost-Free Days: 180+
- Sun: Full Sun
- Mature size: 50 ft tall
- Drought tolerance: Low
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 10-12)
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 Coral Tree 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.
Winter standing
Arizona runs as cold as USDA zone 5, and no sourced winter-hardiness floor is on record for coral tree, so this page does not state whether it overwinters here — and gives no fall establishment date on the strength of a guess. Whether coral tree 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
The zone check says coral tree survives winter in part of Arizona, not across all of it. Whether the season is long enough — and warm enough — is a different question.
Frost-free days
Coral Tree wants 180+ frost-free days; a typical Arizona site sees ~266 (NOAA Regional Climate Centers ACIS, 1991-2020). That leaves comfortable headroom for succession planting.
Chill hours
Coral Tree has no winter-chill requirement — its listed minimum is 0 hours (Growable Ground Plant Database). Arizona typically banks ~2087 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
Coral Tree tolerates a wide pH range (pH 4.5-7.5) — 3 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 5 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, 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. Arizona soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.
What Else to Consider for Coral Tree in Arizona
Zone compatibility tells you about winter cold survival — 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 coral tree — is covered on the Arizona growing guide.
Timing shifts within Arizona
Coral Tree needs about 180 days of frost-free season to complete its cycle. 13 of Arizona’s 15 counties give it that outright. The tightest that does is Navajo County at 192 frost-free days — 12 to spare. Below that line you are transplanting or extending the season, not direct-sowing.
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 coral tree about 86 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"). Coral Tree's 180-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
Coral Tree draws hummingbirds and native bees (high value, Growable Ground Plant Database). Planting it near vegetable beds can lift fruit set on neighboring crops. Outdoors, coral tree 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.
Arizona Cooperative Extension
For Arizona-specific cultivar recommendations, planting calendars, and pest pressure for coral tree, the canonical source is University of Arizona Cooperative Extension. Their fact sheets carry the local trial data we can't generalize across 50 states.
Common Questions About Growing Coral Tree in Arizona
When can I plant Coral Tree 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 Coral Tree, 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 Coral Tree grown in across Arizona?
Arizona spans USDA hardiness zones 5b-10b (USDA ARS PHZM 2023). Coral Tree carries a range of zones 10-12, 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). Coral Tree needs 180+ frost-free days, so check whether your local microclimate runs above or below the state average before settling on a planting date.
How should I amend the soil for Coral Tree in Arizona?
Coral Tree tolerates pH 4.5-7.5 and well (dry spells) drainage (FAO ECOCROP). That is a 3-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 Coral Tree actually grow on my specific land in Arizona?
State-level zone + climate data is a sketch. A Growable Ground parcel report scores coral tree 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 Arizona
State-level data is a sketch. Your Growable Ground report scores coral tree against your parcel's exact soil, sun, drainage, and frost data — not zone averages.
Three things about your lot that Arizona coral tree 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 coral tree average
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