St. Johnsbury, Vermont, sits in USDA hardiness zone 4b — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
The conditions favor cabbage, cranberry, turkish rocket, and collard greens, among others — though every individual site edits that list with its own soil, sun, and drainage.
Even in St. Johnsbury, 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 St. Johnsbury 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 St. Johnsbury — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
St. Johnsbury — the short answer
St. Johnsbury, Vermont: USDA zone 4b, about 164 days between hard freezes, across 8K acres of town.
- USDA zone
- 4b
- USDA PHZM 2023
- Last hard freeze (28°F)
- May 3
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 14
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~164
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 8K 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 4b is St. Johnsbury's average, not your lot's — a low corner or a tree line moves it. Against St. Johnsbury's 164-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in St. Johnsbury
Each reading below is measured for St. Johnsbury itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredSt. Johnsbury runs about 164 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
MeasuredSt. Johnsbury sits in USDA hardiness zone 4b.
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 St. Johnsbury is in
St. Johnsbury sits in the Northeastern Highlands — EPA Level III, inside the wider Northern Forests. That is read at St. Johnsbury's own centroid rather than borrowed from Caledonia County.
What Grows in St. Johnsbury
Every plant below cleared St. Johnsbury's own zone 4b and its 164-day season. Each card opens that plant's Vermont profile. How we score.
Is it too late to plant in St. Johnsbury?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Apr 5; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near May 3 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 14 — long-season crops need about 90 days of runway, quick greens only 30. The tail of the season still works: sixty-day crops into late summer, quick greens after, garlic last of all.
Documented around St. Johnsbury
Survey cells within 31 miles of St. Johnsbury checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 56 miles off. What to watch for.
What's on the federal record near St. Johnsbury
Closest first, within ~10 miles of St. Johnsbury. Listing isn't leaking, and distance isn't exposure.
- VT-SDW 1Nitrate · 1900 ft
- Saint Johnsbury Highway GarageUnderground Storage Tanks · 2200 ft
- QUALITY MOTORS INCBrownfields · 2400 ft
- Gilmour Ford-ChryslerUnderground Storage Tanks · 2400 ft
- Quality Motors IncUnderground Storage Tanks · 2500 ft
- Net Garage (4795-03)Underground Storage Tanks · 2500 ft
- ST JOHNSBURY HIGHWAY DEPTBrownfields · 2500 ft
- RODD ROOFINGBrownfields · 2600 ft
- CONSOLIDATED COMMUNICATIONS ST JOHNSBURYBrownfields · 0.5 mi
- Major L RoddUnderground Storage Tanks · 0.5 mi
- VT-SDW 13Nitrate · 0.6 mi
- ST. JOHNSBURY AUTO MART, INC.Brownfields · 0.6 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from St. Johnsbury'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 St. Johnsbury.
Sources Checked
within ~10 miles of St. Johnsbury
Severity Distribution
within ~10 miles of St. Johnsbury
Highest-Severity Sites
Know Before You Grow
- •Underground tanks leak petroleum as they age — near a former filling station, test the soil.
- •Near a brownfield, raised beds of imported soil give your food clean ground.
- •On a private well, test for nitrates: above 10 mg/L the water needs treatment before irrigating.
Check your specific parcel in St. Johnsbury
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 St. Johnsbury average
Your land is one point inside St. Johnsbury
Everything above resolves to St. Johnsbury as a whole — one PHZM band and one 28°F frost record, read across 8K 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 St. Johnsbury Average
St. Johnsbury Average
- ●USDA Zones 4b, averaged across St. Johnsbury
- ●One soil character for all of St. Johnsbury
- ●Frost dates read at St. Johnsbury's scale: May 3 to Oct 14
YOUR Parcel
- ✓Your exact zone, not St. Johnsbury's 4b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in St. Johnsbury
Pull a site-specific report for your exact address in St. Johnsbury, Vermont — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that St. Johnsbury averages can't show:
We read public map data around St. Johnsbury — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the St. Johnsbury average
How we know this about St. Johnsbury
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 St. Johnsbury’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 St. Johnsbury
When does frost risk typically end in St. Johnsbury?
The last hard freeze (28°F) in St. Johnsbury typically lands around May 3, 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 24.
When is the first frost in St. Johnsbury?
The first hard freeze (28°F) in St. Johnsbury typically arrives around Oct 14, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 30, so the watching starts about Sep 14 — about 164 days after the spring freeze cleared.
How long is the growing season in St. Johnsbury?
Measured between 28°F hard freezes, St. Johnsbury sees about 164 frost-free days — roughly May 3 through Oct 14, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 24 to Sep 30, about 129 days.
Is the soil safe to grow vegetables in St. Johnsbury?
The federal record around St. Johnsbury is a meaningful one — 320 documented sites, mostly Underground Storage Tanks entries (156), the nearest Nitrate record about 0.4 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 St. Johnsbury?
From about Sep 14 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 14 (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 14. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at St. Johnsbury's scale — its 4b band and its 164-day season. Your yard writes its own version of St. Johnsbury'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 St. Johnsbury’s own scale
7 of the readings below were taken at St. Johnsbury's own scale — its own ~164-day season between 28°F freezes, the 8,205 acres it covers and 320 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- St. Johnsbury's own USDA hardiness band, zones 4bUSDA PHZM 2023
- St. Johnsbury's own 28°F hard-freeze dates, about May 3 and Oct 14 and the ~164-day span between themNOAA 1991–2020 Climate Normals
- 320 documented contamination sites on the federal record near St. Johnsbury, the closest Nitrate record about 0.4 miles out from the town centreFederal environmental registers
- St. Johnsbury's boundary and the 8,205 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 4b and a ~164-day seasonGrowable Ground crop-matching engine
- The ecoregion at St. Johnsbury's own centroid, the Northeastern HighlandsUS EPA Level III Ecoregions
- Lanternfly survey cells around St. Johnsbury checked, none carrying a detectionlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so St. Johnsbury's 8,205 acres read through its county's SSURGO summaryfrom Caledonia County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Caledonia County
- The growing challenges every Vermont grower plans around — written at state scale, so they stay on the state guidefrom Vermont
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Caledonia County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among St. Johnsbury's 8,205 acreswhy one lot differs from the next →
- Which side of St. Johnsbury you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 8,205 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Nitrate record about 0.4 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 St. Johnsbury-wide figureread your own land →
More in Vermont
Growing region
Nearby growing guides