Pierce County, in Washington, sits in USDA hardiness zone 8b — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
Crops well matched to these conditions include cabbage, fig, california poppy, and collard greens — though what thrives on any one site still turns on its specific soil, sun, and drainage.
Pierce County lies within the Pacific Northwest — a regional growing area with its own character.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Pierce County holds more than one microclimate.
Soils and elevations shift across Pierce County, so your frost dates and drainage aren't the county average. 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 Pierce County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Pierce County — the short answer
Pierce County, Washington: USDA zone 8b, about 264 days between hard freezes, across 1.1M acres.
- USDA zone
- 8b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 4
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Nov 23
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~264
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 1.1M acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. Hard-freeze dates are county 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 8b is Pierce County's average, not your lot's — a low corner or a tree line moves it. Against Pierce County's 264-day season, see what your own ground reads.
Heat in Pierce County
Across a year, Pierce County accumulates about 1,485 growing degree days above 50°F, about 228 fewer than the middle Washington county — ahead of 14 of Washington’s 39 counties. Degree days are the heat a crop actually gets to work with — more of them is more room to ripen a long-season crop before the freeze closes the window.
Grounded in PRISM Climate Group, Oregon State University — 1991–2020 monthly normals
Soil in Pierce County
Across Pierce County, the ground is predominantly Inceptisols, where Kapowsin, Spanaway, and Alderwood are the most extensive named soil series. The soil is generally well drained with a gravelly sandy loam surface. Topsoil pH runs about 5.2–5.8, strongly acidic. Rainfall drains through hydrologic group B soils.
Soil order
Inceptisols
Drainage
Well drained
Prime farmland
8%
Hydric soils
7%
Soil still varies lot by lot — soil types explained.
How the ground varies across Pierce County
The USDA soil survey maps 41% of Pierce County as well drained — but another 49% drains differently: 21% moderately well drained, 17% somewhat excessively drained.
Kapowsin is the most extensive named soil at 8% of mapped acres, then Spanaway (7%) and Alderwood (5%).
Which of them your own lot sits on is a parcel question, not a county one. Check your address for the survey at your boundary.
What this means for growing in Pierce County
Each reading below is measured for Pierce County itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Drainage
MeasuredThe dominant soils across Pierce County are well drained, in hydrologic group B — ground that drains quickly.
The upside is soil you can work early in spring and roots that never drown; the cost is that fast-draining ground dries out fast and leaches nutrients away before plants can use them.
Work in compost and mulch to hold moisture and feed, and water more often in short doses than deep and rarely.
USDA NRCS SSURGO
Surface pH
MeasuredTopsoil across Pierce County runs about pH 5.2–5.8, on the acidic side.
Blueberries, potatoes, and rhododendrons thrive in it, but most vegetables start locking out nutrients below about pH 6.0 and grow pale and stunted no matter how much you feed them.
A measured lime application raises pH for the crops that need it — but test first, because the right rate depends on your own soil, not the county average.
USDA NRCS SSURGO
Season length
MeasuredPierce County runs about 264 days between hard freezes — close to year-round growing.
Frost is rarely the limit here; winter plantings are as real as summer ones, and the harder question is which crops shrug off the summer heat.
Grow cool-season crops through the mild winter, and choose heat-tolerant varieties for the summer beds.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredPierce County sits in USDA hardiness zone 8b.
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 Pierce County is in
Pierce County spans 2 EPA Level III ecoregions — Cascades (56%) and Puget Lowland (44%). Which one your land falls in changes what grows wild there and how the ground behaves, and a county-wide answer cannot tell you which.
What Grows in Pierce County
We scored all 1,086 plants against Pierce County's own USDA zone 8b and its own 264-day season between hard freezes, using the same matching engine that runs a full parcel report. These cleared both. Sun, soil pH and drainage vary lot by lot — those are the parcel questions below. Each card opens that plant's Washington profile.
Is it too late to plant in Pierce County?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Feb 4; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 4 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 23 — long-season crops need about 90 days of runway, quick greens only 30. With almost year-round growing weather, timing is about heat and rainfall more than frost — some bench is always in play.
Documented around Pierce County
- monarch butterfly2 documented records
Sighting records, so they follow observers as much as insects.
What gets applied to farmland in Pierce County
USGS estimates 6,114 lb of Glyphosate on Pierce County farmland in 2019, its largest by weight, ahead of 2,4-d (1,264 lb) and Bromoxynil (854 lb).
Farmland across the whole county, not any one lot. Check your address for the site-by-site record.
Safe to Grow Here?
What the federal record shows across Pierce County — and how to grow with it.
We checked the federal record across Pierce County — 2,734 documented sites across 8 of the 9 source types we track.
The most significant on record: 75 Superfund sites. Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.
Pierce County carries one of the heavier federal records we track — and that's not a verdict on your yard. Proximity to a documented site is information, not a diagnosis: nothing here says any particular parcel is affected. It does earn one concrete step — before food beds go in the ground, a professional soil test tells you exactly what you're working with, and raised beds with clean imported soil grow well almost anywhere in the meantime.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
What's on the federal record near Pierce County
Closest first, across Pierce County. Listing isn't leaking, and distance isn't exposure.
- ORTING CITY OFPFAS · 0 ft
- ORTING B530590/ORNGWAQ2260Underground Storage Tanks · 0.7 mi
- 18N/05E-09H04 SU-021Nitrate · 1.1 mi
- HOBART BAKERY SYSTEMS ORTINGToxics Release Inventory · 2.5 mi
- BAXTER MANUFACTURINGUnderground Storage Tanks · 2.6 mi
- SQUARE D COMPANY NELCO PLANTUnderground Storage Tanks · 2.7 mi
- Tacoma Silver Mine #42Mining · 2.8 mi
- 19N/05E-32J01Nitrate · 3.0 mi
- ORTING QUARRYUnderground Storage Tanks · 3.1 mi
- SILVERNAIL CONSTRUCTION INCORPORATEDUnderground Storage Tanks · 3.5 mi
- SOLDIERS HOME & COLONYUnderground Storage Tanks · 3.5 mi
- L & M RESTAURANTUnderground Storage Tanks · 3.7 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Pierce County'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 Pierce County.
Severity Distribution
across Pierce County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Pierce County, Superfund runs higher than the national average — 75 sites across Pierce County. 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 Pierce County
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 Pierce County average
Your land is one point inside Pierce County
Everything above resolves to Pierce County as a whole — one PHZM band and one county frost record, read across 1.1M 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 county 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 county average.
Your Lot vs the Pierce County Average
Pierce County Average
- ●USDA Zones 8b, averaged across Pierce County
- ●One soil character for all of Pierce County
- ●Frost dates read at Pierce County's scale: Mar 4 to Nov 23
YOUR Parcel
- ✓Your exact zone, not Pierce County's 8b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Pierce County
Pull a site-specific report for your exact address in Pierce County, Washington — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Pierce County averages can't show:
We read public map data around Pierce County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Pierce County average
How we know this about Pierce County
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at county grain; hard-freeze dates from NOAA 1991–2020 28°F normals at this county’s own record where one resolves, and the labelled statewide window where none does; soils from the USDA NRCS SSURGO survey, area-weighted across the county’s own map units; boundaries and acreage from US Census TIGER/Line 2025; the contamination and pesticide records from the federal sources named in their beats above. Where Pierce County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Pierce County
When does frost risk typically end in Pierce County?
The last hard freeze (28°F) in Pierce County typically lands around Mar 4, 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 Mar 25.
How long is the growing season in Pierce County?
Measured between 28°F hard freezes, Pierce County sees about 264 frost-free days — roughly Mar 4 through Nov 23, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Mar 25 to Nov 9, about 229 days.
Is the soil safe to grow vegetables in Pierce County?
The federal record around Pierce County runs heavier than most — 2,734 documented sites, mostly Underground Storage Tanks entries (1,603), the nearest PFAS record under a tenth of a mile 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.
Everything above is measured at Pierce County's scale — its 8b band and its 264-day season. Your yard writes its own version of Pierce County's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
Will It Grow Here?
Zone fit is the first question — each answer below reads Washington's frost window, season length, and soil profile against the plant's real requirements.
What this page reads at Pierce County’s own scale
9 of the readings below were taken at Pierce County's own scale — its own ~264-day span between 28°F freezes, the 3 most extensive soil series mapped here and 2,734 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Pierce County's own USDA hardiness band, zones 8bUSDA PHZM 2023
- Pierce County's own 28°F hard-freeze dates and its ~264-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Pierce CountyUSDA NRCS SSURGO
- 2,734 documented contamination sites inside the county boundary, distance-sorted from its center — the closest PFAS record under a tenth of a mile outFederal environmental registers
- Pierce County's boundary and the 1,067,535 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 8b and a ~264-day seasonGrowable Ground crop-matching engine
- The 2 ecoregions Pierce County spans, Cascades the largestUS EPA Level III Ecoregions
- Open occurrence records documented in Pierce County for a tracked speciesGBIF derived datasets (CC0 / CC BY 4.0)
- Which agricultural compounds go onto Pierce County farmland, and roughly how muchUSGS NAWQA EPest county estimates
Inherited from a wider read
- The growing challenges every Washington grower plans around — written at state scale, so they stay on the state guidefrom Washington
What this page can’t tell you
- How the season shifts across Pierce County — the ~264 days above is one reading at its centre; the 12 towns below each carry their owntowns in this county →
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Pierce County's 1,067,535 acreswhy one lot differs from the next →
- Which of those 2,734 documented sites actually reaches your soil — that needs your address, the wind, and the groundwater directionhow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — none of it survives being averaged over Pierce Countyread your own land →