Unlikely — Zone Mismatch
Panama rubber tree (zones 12-12) does not overlap with California's zone range (4b-11a). Growing outdoors is unlikely without significant protection.
One zone short — what would close it
Panama Rubber Tree is hardy to zone 12, and the warmest ground in California is zone 11 — 1 zone short. Planted in open ground it will not survive a California winter. To grow it here, grow panama rubber tree in a hoop house or unheated greenhouse — its modeled 1.5-zone lift covers this gap.
A hoop house or unheated greenhouse is the lift this needs. How a greenhouse changes what you can grow →
Zone math from 12-12 (plant) against 5-11 (California). Lift modeled by crop_engine.GREENHOUSE_ZONE_MODIFIER_BY_SUBTYPE['hoop_house'] (+1.5 zones) via api/fast_sections.py Unlock Engine v2.
Panama Rubber Tree in California — the short answer
Panama Rubber Tree in California: hardy in zones 12–12, full sun.
- Plant zones
- 12-12
- Hardy to zone 12a: Tropical Plants Database (Useful Tropical Plants) lists 10 °C, converted to zone 12a, checked Oct 2026. Ceiling: our plant database.
- California zones
- 4b-11a
- USDA PHZM 2023
- Frost window
- Jan 19 - Mar 19 – Nov 29 - Dec 12
- NOAA RCC ACIS 1991-2020, 28°F
- Shortest county season
- 108 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.
California spans zones 4b-11a, 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 panama rubber tree 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
California is not one climate
California’s winter-low ladder runs across 58 counties, from zone 6 in Mono County to zone 10.5 in San Francisco County. That is 45°F between the two counties’ average coldest night — the difference between panama rubber tree overwintering in the ground and coming under cover.
The middle half of 58 counties runs 9–9.5 zones, with a median of 9.5 zones — a 4.5-zone span end to end.
Measured across 58 California 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 Panama Rubber Tree Stands in California
Panama Rubber Tree is rated for zones 12–12 — a cold floor USDA puts at 50 to 60°F. No California 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 California winters, not about panama rubber tree.
Below the zone 12 floor
58 counties
- Mono County · zone 6a
- Alpine County · zone 6b
- Lassen County · zone 7a
3 of 58 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
Panama Rubber Tree Needs
- USDA Zones: 12-12
- Sun: Full Sun
California Has
- USDA Zones: 4b-11a
- Last Hard Freeze (28°F): Jan 19 - Mar 19
- First Hard Freeze (28°F): Nov 29 - Dec 12
- Annual Rainfall: 5-80 inches
- Common Soils: Alluvial clay, Sandy loam, Adobe clay
Plant Zone Range (zones 12-12)
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 Panama Rubber Tree in California
The frost window
Across California, the last spring hard freeze (28°F) clears between Jan 19 and Mar 19, and the first fall hard freeze lands between Nov 29 and Dec 12 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 255-day window you can count on — up to 327 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
California runs as cold as USDA zone 4, and no sourced winter-hardiness floor is on record for panama rubber tree, so this page does not state whether it overwinters here — and gives no fall establishment date on the strength of a guess. Whether panama rubber tree is a permanent planting or a replant-every-spring crop for you turns on your own zone within California; check its hardiness range against that before treating it as long-lived ground.
Timing tuned to sub-state frost dates — Mono 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.
Soil + Drainage Fit
Panama Rubber Tree likes near-neutral soil (pH 4.5-7). That's the common-ground band across California's alluvial 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 5 and 6 — worth knowing before you decide whether a California soil test result is a problem or just a number. Drainage matters: this plant wants well (dry spells). If your California site is heavier clay or sits in a low spot, a raised bed lifts the roots above wet ground, or work in compost.
Your land, not the state average
California's soils run mostly loam, but SSURGO maps the series, texture, and drainage under your exact parcel. Panama Rubber Tree 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 panama rubber tree 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. California soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.
What Else to Consider for Panama Rubber Tree in California
Zone compatibility tells you about winter cold survival — but California growers also need to think about:
Drought is a persistent challenge — irrigation is essential in most regions
Wildfire risk affects rural and foothill properties
Adobe clay soils in valleys drain poorly without amendment
Wide climate variation means plant selection is highly location-specific
Growing panama rubber tree here specifically
Panama Rubber Tree sends deep roots and rates to zones 12–12, but much of California sits on slow-draining, restrictive ground (SSURGO hydrologic group D) that forks and stunts them.
Loosen a deep, stone-free bed for panama rubber tree 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 California grower, not just panama rubber tree — is covered on the California growing guide.
Timing shifts within California
California isn't one climate. In Mono County, the last hard freeze (28°F) holds until about Jun 4 — roughly 120 days later than the recorded state median — so plant panama rubber tree to your county's window, not the statewide date.
County last-freeze dates: NOAA Regional Climate Centers ACIS (1991-2020), county 28°F freeze (earlier than the folk 32°F "last frost"). A parcel report resolves your address's own frost dates.
Where in California Panama Rubber Tree Is Zone-Hardy
Panama Rubber Tree is rated for USDA zones 12–12. No California county reaches it. Even San Francisco County, the state’s mildest winter at zone 10b, sits below the plant’s zone 12 floor — so in open ground this one needs winter protection here, or a container that comes under cover.
Across those 58 counties California’s winter-low ladder runs from zone 6a in Mono County to zone 10b in San Francisco County — 4.5 USDA zones of spread, which is 45°F between the two counties’ average coldest night of the year. None of that range reaches the band panama rubber tree needs, so here the statewide answer really is the answer.
County hardiness zones: USDA Plant Hardiness Zone Map (PHZM) 2023, per county. Panama Rubber Tree’s zone 12–12 band: Hardy to zone 12a: Tropical Plants Database (Useful Tropical Plants) lists 10 °C, converted to zone 12a, checked Oct 2026. Ceiling: our plant database.. A parcel report resolves your address’s own zone and frost dates rather than its county’s.
Good to Know Before You Plant Panama Rubber Tree
Panama Rubber Tree is listed as toxic to dogs, cats (sap) at a mild level. (Source: Cornell Poisonous Plants Database.) Most listed plants only cause brief upset — a raised bed or a fenced corner usually keeps curious pets clear.
California Cooperative Extension
For California-specific cultivar recommendations, planting calendars, and pest pressure for panama rubber tree, the canonical source is UC Agriculture and Natural Resources. Their fact sheets carry the local trial data we can't generalize across 50 states.
Common Questions About Growing Panama Rubber Tree in California
When can I plant Panama Rubber Tree in California?
California's last spring hard freeze (28°F) clears between Jan 19 and Mar 19, and the first fall hard freeze lands between Nov 29 and Dec 12 (NOAA Regional Climate Centers ACIS, 1991-2020). No sourced winter-hardiness floor is on record for Panama Rubber Tree, so this page does not state whether it overwinters in California 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 Panama Rubber Tree grown in across California?
California spans USDA hardiness zones 4b-11a (USDA ARS PHZM 2023). Panama Rubber Tree is listed for zones 12-12, which do not overlap them, so there is no zone in California where this page can call outdoor growing reliable. A parcel report resolves your own address's zone.
How many frost-free days does a typical California site have?
A typical California site sees ~317 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Panama Rubber Tree needs 330+ 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 Mono, the freeze-free season runs shorter than the state average, so verify your own county's window.
How should I amend the soil for Panama Rubber Tree in California?
Panama Rubber Tree prefers pH 4.5-7 and well (dry spells) drainage (FAO ECOCROP). That sits in the common-ground band across California soils — a 30-minute soil test from a local Extension lab confirms it for your specific site.
Will Panama Rubber Tree actually grow on my specific land in California?
State-level zone + climate data is a sketch. A Growable Ground parcel report scores panama rubber tree 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 California
State-level data is a sketch. Your Growable Ground report scores panama rubber tree against your land's mapped soil, modelled sun, drainage, and frost data — not zone averages.
Three things about your lot that California panama rubber tree averages can't show:
We read public map data around California — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the California panama rubber tree average
Explore More
Growing guides for panama rubber tree
Explore California county by county
California carries 58 counties with their own USDA zone — a sample of the growing pages for panama rubber tree there:
Where else panama rubber tree grows
Panama Rubber Tree's zone band crosses state lines — these are the states closest to California 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 California
California has a growing page for 1,041 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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