Sumpter, Oregon, sits in USDA hardiness zone 6a — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
Crops well matched to these conditions include cabbage, blackberry, california poppy, and collard greens — though what thrives on any one site still turns on its specific soil, sun, and drainage.
Even in Sumpter, 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 Sumpter 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 Sumpter — soil, climate, flood, and parcel records. How we handle your address.
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Sumpter — the short answer
Sumpter, Oregon: USDA zone 6a, about 139 days between hard freezes, across 1K acres of city.
- USDA zone
- 6a
- USDA PHZM 2023
- Last hard freeze (28°F)
- May 17
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 3
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~139
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 1K 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 Sumpter's average, not your lot's — a low corner or a tree line moves it. Against Sumpter's 139-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Sumpter
Each reading below is measured for Sumpter itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredSumpter runs about 139 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
MeasuredSumpter 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 Sumpter is in
Sumpter sits in the Blue Mountains — EPA Level III, inside the wider Northwestern Forested Mountains. That is read at Sumpter's own centroid rather than borrowed from Baker County.
What Grows in Sumpter
Every plant below cleared Sumpter's own zone 6a and its 139-day season. Each card opens that plant's Oregon profile. How we score.
Is it too late to plant in Sumpter?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Apr 19; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near May 17 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 3 — long-season crops need about 90 days of runway, quick greens only 30. Even here the calendar’s edges hold value: thirty-day greens late in the window, then garlic and a rested bed for spring.
What's on the federal record near Sumpter
Closest first, within ~10 miles of Sumpter. Listing isn't leaking, and distance isn't exposure.
- STAGE STOP SERVICE STATIONUnderground Storage Tanks · 1600 ft
- Sumpter DredgesMining · 2600 ft
- Consuelo Oregon MinesMining · 1.2 mi
- GardnerMining · 1.7 mi
- ANDERSON KEYLOCKUnderground Storage Tanks · 1.8 mi
- Gray RockMining · 4.8 mi
- Mayflower ProspectMining · 4.8 mi
- SUMPTER VALLEY RAILROAD PARKBrownfields · 4.8 mi
- Mountain BelleMining · 5.1 mi
- GOLCONDA MINESuperfund · 5.3 mi
- Brooklyn MineMining · 5.3 mi
- GolcondaMining · 5.3 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Sumpter'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 Sumpter.
Total Sites
94
within ~10 miles of Sumpter
Risk Level
High
Highest-severity
7 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Sumpter
Severity Distribution
within ~10 miles of Sumpter
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Sumpter, two things run higher than the national average within ~10 miles of Sumpter — Mining (84 sites) and Superfund (7 sites). 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.
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 Sumpter
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 Sumpter average
Your land is one point inside Sumpter
Everything above resolves to Sumpter as a whole — one PHZM band and one 28°F frost record, read across 1K 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 city 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 Sumpter Average
Sumpter Average
- ●USDA Zones 6a, averaged across Sumpter
- ●One soil character for all of Sumpter
- ●Frost dates read at Sumpter's scale: May 17 to Oct 3
YOUR Parcel
- ✓Your exact zone, not Sumpter's 6a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Sumpter
Pull a site-specific report for your exact address in Sumpter, Oregon — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Sumpter averages can't show:
We read public map data around Sumpter — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Sumpter average
How we know this about Sumpter
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this city’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Sumpter’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 city grain anywhere on this page — there is no city-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 Sumpter
When does frost risk typically end in Sumpter?
The last hard freeze (28°F) in Sumpter typically lands around May 17, 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 7.
When is the first frost in Sumpter?
The first hard freeze (28°F) in Sumpter typically arrives around Oct 3, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 19, so the watching starts about Sep 3 — about 139 days after the spring freeze cleared.
How long is the growing season in Sumpter?
Measured between 28°F hard freezes, Sumpter sees about 139 frost-free days — roughly May 17 through Oct 3, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Jun 7 to Sep 19, about 104 days.
Is the soil safe to grow vegetables in Sumpter?
The federal record around Sumpter runs heavier than most — 94 documented sites, mostly Mining entries (84), 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 gardeners stretch the season in Sumpter?
With about 139 frost-free days between hard freezes, Sumpter 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 167 to 195 days — and cold frames or low tunnels buy more. Starting transplants indoors ahead of the May 17 hard-freeze normal stretches the season without touching the calendar.
Everything above is measured at Sumpter's scale — its 6a band and its 139-day season. Your yard writes its own version of Sumpter'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 Sumpter’s own scale
6 of the readings below were taken at Sumpter's own scale — its own ~139-day season between 28°F freezes, the 1,396 acres it covers and 94 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Sumpter's own USDA hardiness band, zones 6aUSDA PHZM 2023
- Sumpter's own 28°F hard-freeze dates, about May 17 and Oct 3 and the ~139-day span between themNOAA 1991–2020 Climate Normals
- 94 documented contamination sites on the federal record near Sumpter, the closest Underground Storage Tanks record about 0.3 miles out from the town centreFederal environmental registers
- Sumpter's boundary and the 1,396 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6a and a ~139-day seasonGrowable Ground crop-matching engine
- The ecoregion at Sumpter's own centroid, the Blue MountainsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Sumpter's 1,396 acres read through its county's SSURGO summaryfrom Baker County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Baker County
- The growing challenges every Oregon grower plans around — written at state scale, so they stay on the state guidefrom Oregon
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Baker County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Sumpter's 1,396 acreswhy one lot differs from the next →
- Which side of Sumpter you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 1,396 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 Sumpter-wide figureread your own land →
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