Lyons, Colorado, sits in USDA hardiness zone 6a — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
These conditions suit cabbage, blackberry, california poppy, and collard greens — a starting list any specific site will trim or extend with its own soil, sun, and drainage.
Even in Lyons, no two yards are alike.
A low spot, a south-facing slope, or a stand of trees moves the frost date and sun across a single Lyons lot. Enter your address and we'll score 1,086 plants against your land's actual soil, sun, and frost.
We read public map data around Lyons — soil, climate, flood, and parcel records. How we handle your address.
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Lyons — the short answer
Lyons, Colorado: USDA zone 6a, about 178 days between hard freezes, across 873 acres of town.
- USDA zone
- 6a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 22
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 17
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~178
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 873 acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. Hard-freeze dates are this town’s own 28°F normals: light frosts run a few weeks past them, and tender transplants usually wait 2–3 weeks after the last hard freeze.
Hardiness Zone Range
Zone 6a is Lyons's average, not your lot's — a low corner or a tree line moves it. Against Lyons's 178-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Lyons
Each reading below is measured for Lyons itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredLyons runs about 178 days between hard freezes — a moderate growing season.
There is room for the full run of cool-season crops plus a warm-season main crop, but the calendar is tight enough that a late spring or early fall frost still decides how much finishes.
Time warm-season transplants to your last hard freeze, and a few weeks of season extension turns a near-miss harvest into a sure one.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredLyons sits in USDA hardiness zone 6a.
The zone sets which perennials, shrubs, and fruit trees live through an average winter here — a plant rated for a colder zone is a safe bet, one rated warmer needs winter protection or gets treated as an annual.
Match perennials and fruit to the zone before you buy, so nothing you plant is a gamble against the cold.
USDA PHZM 2023
The kind of country Lyons is in
Lyons sits in the Southern Rockies — EPA Level III, inside the wider Northwestern Forested Mountains. That is read at Lyons's own centroid rather than borrowed from Boulder County.
What Grows in Lyons
Every plant below cleared Lyons's own zone 6a and its 178-day season. Each card opens that plant's Colorado profile. How we score.
Is it too late to plant in Lyons?
For most of the year, no — what changes is which crops still fit the days remaining. Cool-season crops can go in from around Mar 25; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 22 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 17 — long-season crops need about 90 days of runway, quick greens only 30. Late in the year the fall bench takes over — quick greens, radishes, and garlic that repays you next summer.
What's on the federal record near Lyons
Closest first, within ~10 miles of Lyons. Listing isn't leaking, and distance isn't exposure.
- Ye Old Pump Shop Rexoco #30Underground Storage Tanks · 550 ft
- Town Of LyonsUnderground Storage Tanks · 700 ft
- Walter J KindermanUnderground Storage Tanks · 850 ft
- Ideal Cement Co Lyons TerminalUnderground Storage Tanks · 950 ft
- CST Metro LLC DBA Corner Store #635Underground Storage Tanks · 1600 ft
- Lyons Middle/senior Hi SchoolUnderground Storage Tanks · 1600 ft
- SB00307019ABCA SITE 033Nitrate · 2300 ft
- SB00307019BADB SITE 034Nitrate · 2400 ft
- PORE WATER AT 06724000Nitrate · 0.6 mi
- Loukonen BrothersUnderground Storage Tanks · 0.6 mi
- SB00307019BDCA SITE C59 DUP2Nitrate · 0.7 mi
- CDOT LyonsUnderground Storage Tanks · 0.7 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Lyons's center, not your beds. Run your own address for what's upwind of you specifically.
Environmental Intelligence
The counts behind that headline — every source type on the record near Lyons.
Total Sites
324
within ~10 miles of Lyons
Risk Level
High
Highest-severity
5 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Lyons
Severity Distribution
within ~10 miles of Lyons
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Lyons, two things run higher than the national average within ~10 miles of Lyons — Mining (32 sites) and Superfund (5 sites). 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.
Superfund: Superfund sites represent the most severe contamination in the federal system.
Test soil for heavy metals (lead, arsenic, cadmium, mercury) — this is essential near any mining site.
Commission professional soil testing before any food production (test for heavy metals, VOCs, and SVOCs).
Check your specific parcel in Lyons
Get exact proximity distances to contamination sources for your specific parcel — plus soil, sun, drainage, and 1,086 plant recommendations.
25+ data sources read at your address, not the Lyons average
Your land is one point inside Lyons
Everything above resolves to Lyons as a whole — one PHZM band and one 28°F frost record, read across 873 acres. Your parcel is one point inside that footprint. Slope, tree cover, a low spot that pools cold air, and what is in the soil are all resolved at the address, and none of them are visible at town scale. That is the honest boundary of this page, and the reason the next step is a reading of your own ground rather than a better local average.
Your Lot vs the Lyons Average
Lyons Average
- ●USDA Zones 6a, averaged across Lyons
- ●One soil character for all of Lyons
- ●Frost dates read at Lyons's scale: Apr 22 to Oct 17
YOUR Parcel
- ✓Your exact zone, not Lyons's 6a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Lyons
Pull a site-specific report for your exact address in Lyons, Colorado — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Lyons averages can't show:
We read public map data around Lyons — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Lyons average
How we know this about Lyons
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this town’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Lyons’s own record; boundaries and acreage from US Census TIGER/Line 2025; the contamination records from the federal sources named in their beats above. Soil is not read at town grain anywhere on this page — there is no town-resolution survey in our data, which is why you will find no soil grid here rather than a statewide one wearing a local label. The resolution ledger below names every figure this page inherited.
Common questions about Lyons
When does frost risk typically end in Lyons?
The last hard freeze (28°F) in Lyons typically lands around Apr 22, per NOAA 1991–2020 climate normals — earlier than the light-frost dates most charts quote. That marks the hard freeze, not the last light frost — lighter frosts keep biting past it, which is why tender transplants here wait until about May 13.
When is the first frost in Lyons?
The first hard freeze (28°F) in Lyons typically arrives around Oct 17, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 3, so the watching starts about Sep 17 — about 178 days after the spring freeze cleared.
How long is the growing season in Lyons?
Measured between 28°F hard freezes, Lyons sees about 178 frost-free days — roughly Apr 22 through Oct 17, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 13 to Oct 3, about 143 days.
Is the soil safe to grow vegetables in Lyons?
The federal record around Lyons runs heavier than most — 324 documented sites, mostly Underground Storage Tanks entries (111), the nearest Underground Storage Tanks record about 0.1 miles out — so test the soil before planting food in the ground, and raised beds with clean imported soil grow well in the meantime. Even here, proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what's recorded and where.
How do I protect my plants from frost in Lyons?
From about Sep 17 the job here turns from planting to protecting — the last start even a 30-day crop can finish. As the season closes around the first 28°F hard freeze near Oct 17 (NOAA 1991–2020 climate normals), three moves buy time: row cover or an old sheet over tender plants on still, clear nights; water the soil the afternoon before a freeze, so it holds warmth overnight; and harvest tomatoes, peppers and basil before Oct 17. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Lyons's scale — its 6a band and its 178-day season. Your yard writes its own version of Lyons's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
What this page reads at Lyons’s own scale
6 of the readings below were taken at Lyons's own scale — its own ~178-day season between 28°F freezes, the 873 acres it covers and 324 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Lyons's own USDA hardiness band, zones 6aUSDA PHZM 2023
- Lyons's own 28°F hard-freeze dates, about Apr 22 and Oct 17 and the ~178-day span between themNOAA 1991–2020 Climate Normals
- 324 documented contamination sites on the federal record near Lyons, the closest Underground Storage Tanks record about 0.1 miles out from the town centreFederal environmental registers
- Lyons's boundary and the 873 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6a and a ~178-day seasonGrowable Ground crop-matching engine
- The ecoregion at Lyons's own centroid, the Southern RockiesUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Lyons's 873 acres read through its county's SSURGO summaryfrom Boulder County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Boulder County
- The growing challenges every Colorado grower plans around — written at state scale, so they stay on the state guidefrom Colorado
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Boulder County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Lyons's 873 acreswhy one lot differs from the next →
- Which side of Lyons you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 873 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.1 miles out, measured from the town centrehow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — measured at your address, and averaged away by any Lyons-wide figureread your own land →
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