South River, New Mexico, sits in USDA hardiness zone 7a — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
On paper, cabbage, pawpaw, california poppy, and collard greens all suit these conditions — on the ground, soil, sun, and drainage make the final call.
Even in South River, 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 South River 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 South River — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
South River — the short answer
South River, New Mexico: USDA zone 7a, about 185 days between hard freezes, across 5K acres of town.
- USDA zone
- 7a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 20
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 22
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~185
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 5K 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 South River's average, not your lot's — a low corner or a tree line moves it. Against South River's 185-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in South River
Each reading below is measured for South River itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredSouth River runs about 185 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
MeasuredSouth River 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 South River is in
South River sits in the Arizona/New Mexico Plateau — EPA Level III, inside the wider North American Deserts. That is read at South River's own centroid rather than borrowed from San Juan County.
What Grows in South River
Every plant below cleared South River's own zone 7a and its 185-day season. Each card opens that plant's New Mexico profile. How we score.
Is it too late to plant in South River?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Mar 23; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 20 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 22 — 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 South River
Closest first, within ~10 miles of South River. Listing isn't leaking, and distance isn't exposure.
- 30N.12W.23.443 4Nitrate · 2500 ft
- SAN JUAN COUNTY LANDFILLBrownfields · 1.3 mi
- AZTEC FACILITYBrownfields · 1.6 mi
- CHAMPION TECHNOLOGIES INCToxics Release Inventory · 1.6 mi
- TUBOSCOPE INSPECTION FACILITYBrownfields · 1.9 mi
- TUBOSCOPE INSPECTION FACILITYToxics Release Inventory · 1.9 mi
- CIRCLE K STORE #3586Underground Storage Tanks · 1.9 mi
- CIRCLE K 1436Underground Storage Tanks · 1.9 mi
- AQUA MOSS LLCToxics Release Inventory · 2.1 mi
- HILCORP ENERGYBrownfields · 2.1 mi
- CHAVEZ JOE RUnderground Storage Tanks · 2.2 mi
- SUNDIAL STORE 12Underground Storage Tanks · 2.3 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from South River'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 South River.
Sources Checked
within ~10 miles of South River
Severity Distribution
within ~10 miles of South River
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around South River, Superfund runs higher than the national average — 7 sites within ~10 miles of South River. Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
Superfund: Superfund sites represent the most severe contamination in the federal system.
Commission professional soil testing before any food production (test for heavy metals, VOCs, and SVOCs).
Check your specific parcel in South River
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 South River average
Your land is one point inside South River
Everything above resolves to South River as a whole — one PHZM band and one 28°F frost record, read across 5K 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 South River Average
South River Average
- ●USDA Zones 7a, averaged across South River
- ●One soil character for all of South River
- ●Frost dates read at South River's scale: Apr 20 to Oct 22
YOUR Parcel
- ✓Your exact zone, not South River's 7a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in South River
Pull a site-specific report for your exact address in South River, New Mexico — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that South River averages can't show:
We read public map data around South River — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the South River average
How we know this about South River
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 South River’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 South River
When does frost risk typically end in South River?
The last hard freeze (28°F) in South River typically lands around Apr 20, 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 11.
When is the first frost in South River?
The first hard freeze (28°F) in South River typically arrives around Oct 22, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 8, so the watching starts about Sep 22 — about 185 days after the spring freeze cleared.
How long is the growing season in South River?
Measured between 28°F hard freezes, South River sees about 185 frost-free days — roughly Apr 20 through Oct 22, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 11 to Oct 8, about 150 days.
Is the soil safe to grow vegetables in South River?
The federal record around South River is a meaningful one — 566 documented sites, mostly Underground Storage Tanks entries (288), the nearest Nitrate record about 0.5 miles out — so a soil test before new food beds is a sensible precaution here, not a reason to hold back from growing. Remember that proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what sits where.
How do I protect my plants from frost in South River?
From about Sep 22 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 22 (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 22. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at South River's scale — its 7a band and its 185-day season. Your yard writes its own version of South River'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 South River’s own scale
6 of the readings below were taken at South River's own scale — its own ~185-day season between 28°F freezes, the 5,461 acres it covers and 566 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- South River's own USDA hardiness band, zones 7aUSDA PHZM 2023
- South River's own 28°F hard-freeze dates, about Apr 20 and Oct 22 and the ~185-day span between themNOAA 1991–2020 Climate Normals
- 566 documented contamination sites on the federal record near South River, the closest Nitrate record about 0.5 miles out from the town centreFederal environmental registers
- South River's boundary and the 5,461 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7a and a ~185-day seasonGrowable Ground crop-matching engine
- The ecoregion at South River's own centroid, the Arizona/New Mexico PlateauUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so South River's 5,461 acres read through its county's SSURGO summaryfrom San Juan County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom San Juan County
- The growing challenges every New Mexico grower plans around — written at state scale, so they stay on the state guidefrom New Mexico
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom San Juan County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among South River's 5,461 acreswhy one lot differs from the next →
- Which side of South River you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 5,461 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Nitrate record about 0.5 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 South River-wide figureread your own land →