Yes — Strong Match
Christmas fern (zones 3-9) covers every zone Idaho contains (3b-8a), so hardiness is not what limits it anywhere in the state.
Christmas Fern in Idaho — the short answer
Christmas Fern in Idaho: hardy in zones 3–9, part sun, against a state median of ~160 frost-free days.
- Plant zones
- 3-9
- 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
- Idaho zones
- 3b-8a
- USDA PHZM 2023
- Frost window
- Apr 26 - May 17 – Oct 1 - Oct 17
- NOAA RCC ACIS 1991-2020, 28°F
- Shortest county season
- 94 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.
Idaho spans zones 3b-8a, but your yard has its own microclimate — slope, trees, and low spots shift frost and sun across a single parcel. Enter your address and we'll score christmas fern against your land's actual soil, sun, and frost.
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Idaho is not one climate
A single Idaho answer averages 44 counties whose growing seasons are 122 days apart — from 94 frost-free days in Valley County to 216 in Nez Perce County. Which end of that your land sits nearer changes what christmas fern can finish before the first hard freeze.
The middle half of 44 counties runs 133–174 days, with a median of 159 days — a 122-day span end to end.
Measured across 44 Idaho 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.
Where in Idaho Fits Best
Even within Idaho's zones 3b-8a, county microclimates differ enough to change what thrives. These counties carry the closest zone match for christmas fern (USDA PHZM 2023):
Zone Comparison
Christmas Fern Needs
- USDA Zones: 3-9
- Sun: Part Sun
- Mature size: 2 ft tall
- Drought tolerance: Medium
Idaho Has
- USDA Zones: 3b-8a
- Last Hard Freeze (28°F): Apr 26 - May 17
- First Hard Freeze (28°F): Oct 1 - Oct 17
- Annual Rainfall: 8-35 inches
- Common Soils: Volcanic ash, Silt loam, Sandy loam
Plant Zone Range (zones 3-9)
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 Christmas Fern in Idaho
The frost window
Across Idaho, the last spring hard freeze (28°F) clears between Apr 26 and May 17, and the first fall hard freeze lands between Oct 1 and Oct 17 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 137-day window you can count on — up to 174 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.
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
Drainage requirement: poorly (saturated >50% of year). A soil-survey lookup (NRCS SSURGO) flags whether your specific site matches.
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. Idaho soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.
What Else to Consider for Christmas Fern in Idaho
Zone compatibility tells you about winter cold survival — but Idaho growers also need to think about:
Short growing season at higher elevations
Arid conditions require irrigation in most of the state
Cold winter snaps can reach -30F in mountain valleys
What to actually do about these — and the constraints that apply to every Idaho grower, not just christmas fern — is covered on the Idaho growing guide.
Where in Idaho Christmas Fern Is Zone-Hardy
Christmas Fern is rated for USDA zones 3–9. Every one of Idaho’s 44 counties sits inside that band — from Bear Lake County at zone 5a to Payette County at zone 7a — so winter cold is not what decides this plant anywhere in the state. What is left to vary is your own parcel: slope, shelter and cold-air drainage routinely move a site half a zone either way from the county figure.
Across those 44 counties Idaho’s winter-low ladder runs from zone 5a in Bear Lake County to zone 7a in Payette County — 2 USDA zones of spread, which is 20°F between the two counties’ average coldest night of the year. That is why a statewide hardiness answer is where you start and not where you finish.
The planting window moves with it. Valley County holds its last hard freeze (28°F) until about Jun 14, while Nez Perce County is clear by Apr 1 — 74 days apart. Set christmas fern out on your county’s date, not the state’s.
County hardiness zones: USDA Plant Hardiness Zone Map (PHZM) 2023, per county. County last-freeze dates: NOAA Regional Climate Centers ACIS (1991-2020), county 28°F killing freeze — earlier than the folk 32°F "last frost". Christmas Fern’s zone 3–9 band: USDA PLANTS / Growable Ground plant database. A parcel report resolves your address’s own zone and frost dates rather than its county’s.
Idaho Cooperative Extension
For Idaho-specific cultivar recommendations, planting calendars, and pest pressure for christmas fern, the canonical source is University of Idaho Extension. Their fact sheets carry the local trial data we can't generalize across 50 states.
Is Christmas Fern native to Idaho?
Christmas Fern is native to parts of the Lower 48, but the USDA PLANTS Database (accessed 2026-07-01) does not document a native range in Idaho. It can still earn a place in a Idaho garden — the zone comparison above tells you whether it will thrive.
Looking for plants that belong here? The Idaho 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 Christmas Fern in Idaho
When can I plant Christmas Fern in Idaho?
Idaho's last spring hard freeze (28°F) clears between Apr 26 and May 17, and the first fall hard freeze lands between Oct 1 and Oct 17 (NOAA Regional Climate Centers ACIS, 1991-2020). Time outdoor planting to after the last hard freeze for your specific site — a further two to three weeks for anything tender — and count back from those dates for transplant scheduling.
What hardiness zone is Christmas Fern grown in across Idaho?
Idaho spans USDA hardiness zones 3b-8a (USDA ARS PHZM 2023). Christmas Fern carries a range of zones 3-9, so the overlap zones are where outdoor growing is most reliable.
How many frost-free days does a typical Idaho site have?
A typical Idaho site sees ~160 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Christmas Fern should be matched against that window, so check whether your local microclimate runs above or below the state average before settling on a planting date.
Is Christmas Fern native to Idaho?
Christmas Fern is native to parts of the Lower 48, but the USDA PLANTS Database (accessed 2026-07-01) does not document a native range in Idaho. It can still earn a place in a Idaho garden — the zone comparison above tells you whether it will thrive.
Will Christmas Fern actually grow on my specific land in Idaho?
State-level zone + climate data is a sketch. A Growable Ground parcel report scores christmas fern 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 Idaho
State-level data is a sketch. Your Growable Ground report scores christmas fern against your parcel's exact soil, sun, drainage, and frost data — not zone averages.
Three things about your lot that Idaho christmas fern averages can't show:
We read public map data around Idaho — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Idaho christmas fern average
Explore More
Growing guides for christmas fern
Explore Idaho county by county
Idaho carries 44 counties with their own USDA zone — a sample of the growing pages for christmas fern there:
Where else christmas fern grows
Christmas Fern's zone band crosses state lines — these are the states closest to Idaho 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 Idaho
Idaho has a growing page for 893 plants — a rotating sample of the rest of the shelf.
Last updated:

