Loomis, Washington, sits in USDA hardiness zone 7a — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
Growers here do well with cabbage, pawpaw, california poppy, and collard greens — with the usual caveat that any single yard's soil, sun, and drainage cast the deciding vote.
Even in Loomis, 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 Loomis 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 Loomis — soil, climate, flood, and parcel records. How we handle your address.
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Loomis — the short answer
Loomis, Washington: USDA zone 7a, about 198 days between hard freezes, across 562 acres of town.
- USDA zone
- 7a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 9
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 24
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~198
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 562 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 7a is Loomis's average, not your lot's — a low corner or a tree line moves it. Against Loomis's 198-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Loomis
Each reading below is measured for Loomis itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredLoomis runs about 198 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
MeasuredLoomis sits in USDA hardiness zone 7a.
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 Loomis is in
Loomis sits in the North Cascades — EPA Level III, inside the wider Northwestern Forested Mountains. That is read at Loomis's own centroid rather than borrowed from Okanogan County.
What Grows in Loomis
Every plant below cleared Loomis's own zone 7a and its 198-day season. Each card opens that plant's Washington profile. How we score.
Is it too late to plant in Loomis?
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 12; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 9 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 24 — 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 Loomis
Closest first, within ~10 miles of Loomis. Listing isn't leaking, and distance isn't exposure.
- LOOMIS KWIK STOPUnderground Storage Tanks · 1400 ft
- Palmer MountainMining · 2500 ft
- Palmer Mountain TunnelMining · 2600 ft
- Security MineMining · 0.5 mi
- SecurityMining · 0.6 mi
- SHEEP MOUNTAIN CATTLE COMPANYUnderground Storage Tanks · 0.8 mi
- AliceMining · 1.0 mi
- Black Bear MineMining · 1.1 mi
- Black BearMining · 1.1 mi
- RubyMining · 1.4 mi
- Summit MineMining · 1.9 mi
- War Eagle ClaimMining · 1.9 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Loomis'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 Loomis.
Sources Checked
within ~10 miles of Loomis
Severity Distribution
within ~10 miles of Loomis
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Loomis, Mining runs higher than the national average — 173 sites within ~10 miles of Loomis. That's not a problem with your land — it's information about 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.
Test soil for heavy metals (lead, arsenic, cadmium, mercury) — this is essential near any mining site.
Check your specific parcel in Loomis
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 Loomis average
Your land is one point inside Loomis
Everything above resolves to Loomis as a whole — one PHZM band and one 28°F frost record, read across 562 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 Loomis Average
Loomis Average
- ●USDA Zones 7a, averaged across Loomis
- ●One soil character for all of Loomis
- ●Frost dates read at Loomis's scale: Apr 9 to Oct 24
YOUR Parcel
- ✓Your exact zone, not Loomis's 7a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Loomis
Pull a site-specific report for your exact address in Loomis, Washington — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Loomis averages can't show:
We read public map data around Loomis — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Loomis average
How we know this about Loomis
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 Loomis’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 Loomis
When does frost risk typically end in Loomis?
The last hard freeze (28°F) in Loomis typically lands around Apr 9, 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 Apr 30.
When is the first frost in Loomis?
The first hard freeze (28°F) in Loomis typically arrives around Oct 24, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 10, so the watching starts about Sep 24 — about 198 days after the spring freeze cleared.
How long is the growing season in Loomis?
Measured between 28°F hard freezes, Loomis sees about 198 frost-free days — roughly Apr 9 through Oct 24, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 30 to Oct 10, about 163 days.
Is the soil safe to grow vegetables in Loomis?
The federal record around Loomis runs heavier than most — 181 documented sites, mostly Mining entries (173), the nearest Underground Storage Tanks record about 0.3 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 Loomis?
From about Sep 24 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 24 (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 24. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Loomis's scale — its 7a band and its 198-day season. Your yard writes its own version of Loomis'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 Loomis’s own scale
6 of the readings below were taken at Loomis's own scale — its own ~198-day season between 28°F freezes, the 562 acres it covers and 181 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Loomis's own USDA hardiness band, zones 7aUSDA PHZM 2023
- Loomis's own 28°F hard-freeze dates, about Apr 9 and Oct 24 and the ~198-day span between themNOAA 1991–2020 Climate Normals
- 181 documented contamination sites on the federal record near Loomis, the closest Underground Storage Tanks record about 0.3 miles out from the town centreFederal environmental registers
- Loomis's boundary and the 562 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7a and a ~198-day seasonGrowable Ground crop-matching engine
- The ecoregion at Loomis's own centroid, the North CascadesUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Loomis's 562 acres read through its county's SSURGO summaryfrom Okanogan County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Okanogan County
- The growing challenges every Washington grower plans around — written at state scale, so they stay on the state guidefrom Washington
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Okanogan County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Loomis's 562 acreswhy one lot differs from the next →
- Which side of Loomis you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 562 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.3 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 Loomis-wide figureread your own land →
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