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When to Plant Spinach in Crook County, OR

Spinach is a nutrient-packed cool-season green that grows quickly in spring and fall. It is rich in iron, vitamins, and antioxidants and excellent raw or cooked.

Crook County, Oregon is in USDA Zone 6a. The average last spring frost is June 9 and the first fall frost is September 19, giving you a growing season of approximately 102 days.

At an elevation of 2,233 feet, Crook County receives approximately 21 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85ยฐF, providing good warmth for Spinach during the growing season.

Crook County, OR (Zone 6a) Short season
102 days
Last Spring Frost June 9
102 growing days
First Fall Frost September 19

Crook County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (5 days to spare)
Start indoors: Apr 25 Transplant: May 30 🍅 Harvest: Jul 4 – Sep 5
Recommended (50%) ✓ Fits season (4 days to spare)
Start indoors: May 5 Transplant: Jun 9 🍅 Harvest: Jul 14 – Sep 15
Safe Start (90%) ✓ Fits season (8 days to spare)
Start indoors: May 18 Transplant: Jun 22 🍅 Harvest: Jul 27 – Sep 28

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Crook County

How your county's soil matches Spinach's growing requirements.

Soil pH

Your soil pH (5.7โ€“6.7) is more acidic than Spinach prefers (6.5โ€“7.5). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Crook County is excellent for Spinach โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (5.6%) โ€” Spinach will thrive.

How to Plant Spinach

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Spinach

3
successive plantings in your 102-day season

Sow every 4 weeks. Last sowing by Jul 31 to harvest before frost.

For a dedicated fall crop, sow by Jul 11.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Spinach

Spinach needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.

Month Spinach Needs Rainfall You Supplement Action
Jan โ€” 3.4" 0" โ„๏ธ Dormant
Feb โ€” 2.2" 0" โ„๏ธ Dormant
Mar โ€” 2.2" 0" โ„๏ธ Dormant
Apr โ€” 1.5" 0" โ„๏ธ Dormant
May โ€” 1.2" 0" โ„๏ธ Dormant
Jun 3" 0.9" 2.1" ๐Ÿšฟ Regular watering
Jul 3" 0.3" 2.7" ๐Ÿšฟ Regular watering
Aug 3" 0.4" 2.6" ๐Ÿšฟ Regular watering
Sep 3" 1" 2" ๐Ÿšฟ Regular watering
Oct โ€” 1.6" 0" โ„๏ธ Dormant
Nov โ€” 3.1" 0" โ„๏ธ Dormant
Dec โ€” 3.1" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Junโ€“Sep in Crook County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Spinach Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" โ€” every day above 50ยฐF deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Spinach needs ~584 GDD — county provides 1,402 GDD Excellent fit

Spinach Planting Timeline โ€” Crook County, OR

Spinach Planting Calendar

Activity When Date Range
Start Indoors May 5 May 5 โ€“ May 19
Transplant Outdoors June 9 Jun 9 โ€“ Jun 23
Direct Sow May 26 May 26 โ€“ Jun 16
Harvest July 14 Jul 14 โ€“ Sep 15
Fall Sowing July 11 Jul 11 โ€“ Jul 25

Plant 0.5" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May Start Indoors Direct Sow
June Transplant Outdoors Direct Sow
July Fall Sowing Harvest
August Harvest
September Harvest
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

0.7"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

35โ€“50 days

๐Ÿงช Soil pH

Needs 6.5โ€“7.5 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 6a

๐Ÿ“† Growing Season

102 days in Crook County

Growing Tips for Spinach in Crook County

Direct sow Spinach outdoors after June 09 in Crook County when soil has warmed and frost danger has passed.

General growing tips

Direct sow as soon as soil can be worked in spring. Plant in partial shade for summer crops to delay bolting. Succession plant every 2 weeks for continuous harvest.

Recommended Spinach Varieties for Crook County

Slow-bolting spinach for warm springs โ€” best as fall crop here

Bloomsdale Long Standing Tyee Space

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

๐ŸŒพ Save Your Own Spinach Seeds
Life Cycle Annual
Pollination Wind Pollinated
How to Collect Let plants bolt. Harvest seed stalks when seeds turn tan.
Storage Store airtight; viable 5 years at 35ยฐF, under 45% humidity.

Wind pollinated โ€” isolate 1/2 mile for purity. Easy to let bolt in heat.

Frequently Asked Questions

When should I plant Spinach in Crook County, OR?

Crook County is in Zone 6a with an average last frost of June 9. Plan your Spinach planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Crook County, OR?

Crook County, Oregon is in USDA Hardiness Zone 6a. The average last spring frost is June 9 and first fall frost is September 19.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Crook County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Crook County, OR. Local conditions may vary. Last updated: April 2026.