Empire, Colorado, sits in USDA hardiness zone 5b — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
Well-matched crops include cabbage, cranberry, lavender, and collard greens, and the gap between "grows in the area" and "grows in your yard" is closed by soil, sun, and drainage.
Even in Empire, 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 Empire 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 Empire — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Empire — the short answer
Empire, Colorado: USDA zone 5b, about 131 days between hard freezes, across 187 acres of town.
- USDA zone
- 5b
- USDA PHZM 2023
- Last hard freeze (28°F)
- May 19
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Sep 27
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~131
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 187 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 5b is Empire's average, not your lot's — a low corner or a tree line moves it. Against Empire's 131-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Empire
Each reading below is measured for Empire itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredEmpire runs about 131 days between hard freezes — a short growing season.
Long-maturing crops like melons, sweet potatoes, and winter squash can run out of runway before the first hard freeze, ripening late or not at all.
Lead with fast-maturing varieties, and stretch the season on both ends with cold frames, low tunnels, or a greenhouse.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredEmpire sits in USDA hardiness zone 5b.
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 Empire is in
Empire sits in the Southern Rockies — EPA Level III, inside the wider Northwestern Forested Mountains. That is read at Empire's own centroid rather than borrowed from Clear Creek County.
What Grows in Empire
Every plant below cleared Empire's own zone 5b and its 131-day season. Each card opens that plant's Colorado profile. How we score.
Is it too late to plant in Empire?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Apr 21; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near May 19 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Sep 27 — long-season crops need about 90 days of runway, quick greens only 30. In a season this compact, fast finishers and cold-hardy greens do the late work, and garlic tucked in before the freeze repays you next summer.
What's on the federal record near Empire
Closest first, within ~10 miles of Empire. Listing isn't leaking, and distance isn't exposure.
- Henderson MineUnderground Storage Tanks · 650 ft
- ValeroUnderground Storage Tanks · 700 ft
- Right TunnelMining · 900 ft
- Lady AdelaideMining · 900 ft
- DuluthMining · 900 ft
- Virginia CityMining · 900 ft
- Maud S.Mining · 900 ft
- O.S.StorrsMining · 900 ft
- PegmatiteMining · 900 ft
- PayneMining · 900 ft
- Dead JackMining · 900 ft
- A.C.A.Mining · 900 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Empire'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 Empire.
Sources Checked
within ~10 miles of Empire
Severity Distribution
within ~10 miles of Empire
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Empire, two things run higher than the national average within ~10 miles of Empire — Mining (635 sites) and Superfund (9 sites). It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.
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 Empire
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 Empire average
Your land is one point inside Empire
Everything above resolves to Empire as a whole — one PHZM band and one 28°F frost record, read across 187 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 Empire Average
Empire Average
- ●USDA Zones 5b, averaged across Empire
- ●One soil character for all of Empire
- ●Frost dates read at Empire's scale: May 19 to Sep 27
YOUR Parcel
- ✓Your exact zone, not Empire's 5b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Empire
Pull a site-specific report for your exact address in Empire, Colorado — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Empire averages can't show:
We read public map data around Empire — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Empire average
How we know this about Empire
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 Empire’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 Empire
When does frost risk typically end in Empire?
The last hard freeze (28°F) in Empire typically lands around May 19, 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 Jun 9.
When is the first frost in Empire?
The first hard freeze (28°F) in Empire typically arrives around Sep 27, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 13, so the watching starts about Aug 28 — about 131 days after the spring freeze cleared.
How long is the growing season in Empire?
Measured between 28°F hard freezes, Empire sees about 131 frost-free days — roughly May 19 through Sep 27, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Jun 9 to Sep 13, about 96 days.
Is the soil safe to grow vegetables in Empire?
The federal record around Empire runs heavier than most — 728 documented sites, mostly Mining entries (635), 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 gardeners stretch the season in Empire?
With about 131 frost-free days between hard freezes, Empire rewards the classic extension moves: floating row cover buys roughly two to four extra weeks at each shoulder — on this season that is a working window nearer 159 to 187 days — and cold frames or low tunnels buy more. Starting transplants indoors ahead of the May 19 hard-freeze normal stretches the season without touching the calendar.
Everything above is measured at Empire's scale — its 5b band and its 131-day season. Your yard writes its own version of Empire'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 Empire’s own scale
6 of the readings below were taken at Empire's own scale — its own ~131-day season between 28°F freezes, the 187 acres it covers and 728 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Empire's own USDA hardiness band, zones 5bUSDA PHZM 2023
- Empire's own 28°F hard-freeze dates, about May 19 and Sep 27 and the ~131-day span between themNOAA 1991–2020 Climate Normals
- 728 documented contamination sites on the federal record near Empire, the closest Underground Storage Tanks record about 0.1 miles out from the town centreFederal environmental registers
- Empire's boundary and the 187 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5b and a ~131-day seasonGrowable Ground crop-matching engine
- The ecoregion at Empire's own centroid, the Southern RockiesUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Empire's 187 acres read through its county's SSURGO summaryfrom Clear Creek County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Clear Creek 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 Clear Creek County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Empire's 187 acreswhy one lot differs from the next →
- Which side of Empire you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 187 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 Empire-wide figureread your own land →