What Grows in Happy Valley, Oregon

USDA Zones 4a-5b · 8K acres

Happy Valley, Oregon, sits in USDA hardiness zones 4a-5b — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.

Among the crops suited to this profile: hazelnut, blueberry, kale, and hop. The site-level story — soil, sun, drainage — decides the rest.

Score your parcel · free

Even in Happy Valley, 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 Happy Valley lot. Enter your address and we'll score 1,112 plants against your land's actual soil, sun, and frost.

We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.

No card required · your full report in seconds

Quick Facts

USDA Zones

4a-5b

Last Hard Freeze (28°F)

Mar 6

Clackamas County normal — light frosts run a few weeks later

First Hard Freeze (28°F)

Dec 6

Clackamas County normal — light frosts arrive a few weeks earlier

City Area

8K acres

Hardiness Zone Range

4a
5b
3a (Cold)13b (Hot)

Zone maps are averages across Happy Valley. Your yard's slope, trees, and frost pockets shift what actually grows — see your land's exact reading.

Soil varies lot by lot — soil types explained.

Is it too late to plant in Happy Valley?

Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Feb 6; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 6 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 6 — long-season crops need about 90 days of runway, quick greens only 30. And with a calendar this mild, the honest answer is that planting barely stops — winter opens seasons colder regions never see.

Growing Challenges in Oregon

What an experienced grower plans around here — each one has a move.

West side: excessive rain and overcast skies reduce sun for warm-season crops

Map your sun honestly — a south-facing bed against a light wall recovers a surprising amount of the light the clouds take.

East side: arid conditions (8-15 inches rainfall) require irrigation

East of the Cascades, drip irrigation is infrastructure, not an accessory — plan it before the first planting.

Slug pressure is extreme in western Oregon

Evening patrols, iron-phosphate baits, and dry mulch edges knock slugs back — your extension guide covers the full toolkit.

Mountain areas have very short seasons (60-90 frost-free days)

At 60-90 frost-free days, season extension is the difference between a garden and a gamble — a high tunnel changes the math.

For cultivar selection, pest pressure, and planting-time guidance specific to Oregon, the OSU Extension Service is the authoritative local source.

Environmental Intelligence

Understanding what's nearby helps you make informed decisions about where and how to grow.

Total Sites

2,638

within ~10 miles of Happy Valley

Risk Level

High

Highest-severity

35 Superfund sites

Severity Distribution

within ~10 miles of Happy Valley

High37Moderate444Low2,157

Highest-Severity Sites

Coe Civil Willamette Falls Locks
Superfund · Superfund (Non-NPL)
Color Glass Portland
Superfund · Superfund (Non-NPL)
Former Milwaukie Cleaners
Superfund · Superfund (Non-NPL)
Kronberg Dump
Superfund · Superfund (Non-NPL)
Martin Electric
Superfund · Superfund (Non-NPL)

A note from Gnorman

What an experienced grower watches for around here

In and around Happy Valley, Superfund runs higher than the national average — 35 sites nearby. 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).

Free Report

Check your specific parcel in Happy Valley

Get exact proximity distances to contamination sources for your specific parcel — plus soil, sun, drainage, and 1,112 plant recommendations.

Three things about your exact spot that zone averages miss:

Your soil pHYour frost-free daysYour sun & shade

We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.

25+ data sources analyzed in seconds

Your Specific Parcel Matters

Happy Valley Average

  • USDA Zones 4a-5b
  • Generic soil type for the area
  • State-average frost dates

YOUR Parcel

  • Your exact hardiness zone
  • Your SSURGO soil type & pH
  • Your sun exposure, cast in 3D

See MY Growing Report

Free Report

Read your specific parcel in Happy Valley

Pull a site-specific report for your exact address in Happy Valley, Oregon — soil, sun, drainage, frost risk, and scored plant recommendations.

Three things about your exact spot that zone averages miss:

Your soil pHYour frost-free daysYour sun & shade

We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.

25+ data sources analyzed in seconds

Key Growing Facts for Happy Valley, Oregon

  • USDA Hardiness Zones: 4a-5b (USDA PHZM 2023)
  • Last Hard Freeze (28°F): Mar 6 (clackamas county normal, NOAA 1991–2020 Climate Normals — light frosts can follow for a few weeks)
  • First Hard Freeze (28°F): Dec 6 (clackamas county normal, NOAA 1991–2020 Climate Normals — light frosts can arrive a few weeks earlier)
  • Days Between Hard Freezes: ~275 (clackamas county normal, NOAA 1991–2020 Climate Normals)
  • Land Area: 8K acres (US Census TIGER 2025)

Zone data: USDA ARS Plant Hardiness Zone Map 2023. Climate data: NOAA NCEI. Boundaries: US Census TIGER/Line 2025.

Frequently Asked Questions

What hardiness zone is Happy Valley, Oregon?

Happy Valley sits in USDA hardiness zones 4a-5b, per the USDA Plant Hardiness Zone Map 2023. Zones reflect average annual extreme minimum temperatures from 1991–2020 weather data.

Is it too late to plant in Happy Valley?

Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Feb 6; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 6 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Dec 6 — long-season crops need about 90 days of runway, quick greens only 30. And with a calendar this mild, the honest answer is that planting barely stops — winter opens seasons colder regions never see.

When does frost risk typically end in Happy Valley?

The last hard freeze (28°F) in Happy Valley typically lands around Mar 6, per NOAA 1991–2020 climate normals — an earlier marker than the light-frost dates many planting charts quote. That marks the hard freeze, not the last light frost — light frosts can still bite for a few more weeks, so tender transplants usually wait another 2–3 weeks.

When is the first frost in Happy Valley?

The first hard freeze (28°F) in Happy Valley typically arrives around Dec 6, per NOAA 1991–2020 climate normals — the point most tender summer crops finish. Lighter frosts usually reach a couple of weeks earlier, so watch the forecast from late summer on and harvest or cover tender plants before the first cold night.

What vegetables grow in Happy Valley?

Happy Valley's zones 4a-5b support a wide range — strong performers include Hazelnut, Blueberry, Kale, Hop, and Douglas Fir. What actually takes on any one site comes down to its soil, sun, and drainage, and we score each plant against the real conditions at your address.

Which hardiness zone is Happy Valley, really?

Officially, Happy Valley sits in USDA zones 4a-5b (USDA PHZM 2023) — but a zone is a 30-year average of winter's coldest night across an area, and it can't see any one yard. A south-facing slope, a tree line, or a low frost pocket can shift a single site by half a zone either way, which is why neighboring gardeners often quote different numbers. We read the conditions at your exact address — soil, sun, slope, and frost — and score 1,112 plants against what's actually there.

Is the soil safe to grow vegetables in Happy Valley?

The federal record around Happy Valley runs heavier than most — 2,638 documented sites — 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 Happy Valley?

As the season closes around the first 28°F hard freeze near Dec 6 (NOAA 1991–2020 climate normals), a few moves buy time: cover tender plants with floating row cover or an old sheet on still, clear nights, water the soil the afternoon before a freeze so it holds warmth overnight, and harvest frost-tender crops like tomatoes, peppers, and basil before the first hard night. Hardy greens and root crops shrug off light frost and often sweeten after it, so leave them in.

Everything on this page is a Happy Valley average. Your yard writes its own version — we read soil, sun, drainage, and frost at your exact address. Try it for 14 days — no card required.