Generally — Most Areas
balsam fir (zones 2-6) suits most of Colorado (3b-7b) — zones 3-6 are in range, and the rest of the state is the exception.
Balsam Fir in Colorado — the short answer
Balsam Fir in Colorado: hardy in zones 2–6, part sun, against a state median of ~155 frost-free days.
- Plant zones
- 2-6
- 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
- Colorado zones
- 3b-7b
- USDA PHZM 2023
- Frost window
- Apr 25 - May 19 – Sep 29 - Oct 16
- NOAA RCC ACIS 1991-2020, 28°F
- Shortest county season
- 85 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.
Colorado spans zones 3b-7b, 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 balsam fir 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 full report in seconds
Colorado is not one climate
Colorado’s winter-low ladder runs across 64 counties, from zone 4.5 in Alamosa County to zone 7 in Mesa County. That is 25°F between the two counties’ average coldest night — the difference between balsam fir overwintering in the ground and coming under cover.
The middle half of 64 counties runs 5.5–6 zones, with a median of 5.5 zones — a 2.5-zone span end to end.
Measured across 64 Colorado 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 in Colorado Fits Best
Balsam Fir is rated for zones 2–6 — a cold floor USDA puts at -50 to -40°F. Against Colorado’s 64 counties that band holds in 60 of them, and the line runs at Alamosa County (zone 4b), the coldest county still inside it.
Inside zones 2–6
60 counties
- Jackson County · zone 4b
- Park County · zone 4b
- Routt County · zone 4b
3 of 60 shown
Above the zone 6 ceiling
4 counties
- Baca County · zone 6b
- La Plata County · zone 6b
- Delta County · zone 7a
3 of 4 shown
Too little winter chill rather than too much cold — a low-chill selection is what changes it.
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.
Even within Colorado's zones 3b-7b, county microclimates differ enough to change what thrives. These counties carry the closest zone match for balsam fir (USDA PHZM 2023):
Zone Comparison
Balsam Fir Needs
- USDA Zones: 2-6
- Frost-Free Days: 100+
- Sun: Part Sun
- Mature size: 60 ft tall
- Drought tolerance: Low
Colorado Has
- USDA Zones: 3b-7b
- Last Hard Freeze (28°F): Apr 25 - May 19
- First Hard Freeze (28°F): Sep 29 - Oct 16
- Annual Rainfall: 7-20 inches
- Common Soils: Sandy loam, Clay loam, Alkaline caliche
Plant Zone Range (zones 2-6)
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 Balsam Fir in Colorado
The frost window
Across Colorado, the last spring hard freeze (28°F) clears between Apr 25 and May 19, and the first fall hard freeze lands between Sep 29 and Oct 16 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 133-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.
Winter standing
Colorado runs as cold as USDA zone 3, and no sourced winter-hardiness floor is on record for balsam fir, so this page does not state whether it overwinters here — and gives no fall establishment date on the strength of a guess. Whether balsam fir is a permanent planting or a replant-every-spring crop for you turns on your own zone within Colorado; check its hardiness range against that before treating it as long-lived ground.
Timing tuned to sub-state frost dates — Chaffee 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.
Growing Season Fit
The zone check says balsam fir survives winter in part of Colorado, not across all of it. Whether the season is long enough — and warm enough — is a different question.
Frost-free days
Balsam Fir wants 100+ frost-free days; a typical Colorado site sees ~155 (NOAA Regional Climate Centers ACIS, 1991-2020). That leaves a workable window — start indoors to bank time.
Chill hours
Balsam Fir requires ~1000 chill hours (32-45°F dormancy window). Colorado typically banks ~2500 chill hours per winter (from PRISM 1991-2020 climate normals), which keeps this plant on track.
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
Balsam Fir 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 Colorado. 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 6.5 — worth knowing before you decide whether a Colorado soil test result is a problem or just a number. Drainage matters: this plant wants well (dry spells). If your Colorado site is heavier clay or sits in a low spot, raised beds or amendment with compost solve it.
Your land, not the state average
Colorado's soils run mostly loam, but SSURGO maps the series, texture, and drainage under your exact parcel. Balsam Fir needs about 19 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 balsam fir 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. Colorado soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.
What Else to Consider for Balsam Fir in Colorado
Zone compatibility tells you about winter cold survival — but Colorado growers also need to think about:
Low annual rainfall (7-20 inches) means irrigation is essential nearly everywhere
High altitude UV and temperature swings stress plants
Very short growing season at elevation (60-90 frost-free days above 8,000 ft)
Alkaline soils (pH 7.5-8.5) limit acid-loving plants without amendment
Growing balsam fir here specifically
Colorado's soils run mostly loam (Mollisols), and whether that suits balsam fir's pH 4.5–7.5 preference comes down to your exact parcel, not the statewide picture.
Pull your parcel's SSURGO map unit, test pH, and amend toward balsam fir's 4.5–7.5 target before planting. How to handle it →
What to actually do about these — and the constraints that apply to every Colorado grower, not just balsam fir — is covered on the Colorado growing guide.
Timing shifts within Colorado
Colorado isn't one climate. In Chaffee County, the last hard freeze (28°F) holds until about Jun 12 — roughly 38 days later than the recorded state median — so plant balsam fir to your county's window, not the statewide date.
Balsam Fir needs about 100 days of frost-free season to complete its cycle. 60 of Colorado’s 64 counties give it that outright. The tightest that does is Summit County at 102 frost-free days — 2 to spare. Below that line you are transplanting or extending the season, not direct-sowing.
Across Colorado’s 64 counties the frost-free season runs from 85 days in Chaffee County to 209 days in Mesa County — a spread of 124 days, which is why a single statewide planting date misleads. The median Colorado county sees 155 frost-free days, leaving balsam fir about 55 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"). Balsam Fir's 100-day requirement: USDA PLANTS / Growable Ground plant database (minimum frost-free days). A parcel report resolves your address's own frost dates.
Colorado Cooperative Extension
For Colorado-specific cultivar recommendations, planting calendars, and pest pressure for balsam fir, the canonical source is Colorado State University Extension. Their fact sheets carry the local trial data we can't generalize across 50 states.
Is Balsam Fir native to Colorado?
Balsam Fir is native to parts of the Lower 48, but the USDA PLANTS Database (accessed 2026-07-01) does not document a native range in Colorado. It can still earn a place in a Colorado garden — the zone comparison above tells you whether it will thrive.
Looking for plants that belong here? The Colorado 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 Balsam Fir in Colorado
When can I plant Balsam Fir in Colorado?
Colorado's last spring hard freeze (28°F) clears between Apr 25 and May 19, and the first fall hard freeze lands between Sep 29 and Oct 16 (NOAA Regional Climate Centers ACIS, 1991-2020). No sourced winter-hardiness floor is on record for Balsam Fir, so this page does not state whether it overwinters in Colorado 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 Balsam Fir grown in across Colorado?
Colorado spans USDA hardiness zones 3b-7b (USDA ARS PHZM 2023). Balsam Fir carries a range of zones 2-6, so the overlap zones are where outdoor growing is most reliable.
How many frost-free days does a typical Colorado site have?
A typical Colorado site sees ~155 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Balsam Fir needs 100+ 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 Chaffee, the freeze-free season runs shorter than the state average, so verify your own county's window.
Is Balsam Fir native to Colorado?
Balsam Fir is native to parts of the Lower 48, but the USDA PLANTS Database (accessed 2026-07-01) does not document a native range in Colorado. It can still earn a place in a Colorado garden — the zone comparison above tells you whether it will thrive.
How should I amend the soil for Balsam Fir in Colorado?
Balsam Fir 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 Colorado site — amend for drainage and organic matter first.
Will Balsam Fir actually grow on my specific land in Colorado?
State-level zone + climate data is a sketch. A Growable Ground parcel report scores balsam fir 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 Colorado
State-level data is a sketch. Your Growable Ground report scores balsam fir against your parcel's exact soil, sun, drainage, and frost data — not zone averages.
Three things about your lot that Colorado balsam fir averages can't show:
We read public map data around Colorado — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Colorado balsam fir average
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
Last updated: