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When to Plant Cauliflower in Ferry County, WA

Cauliflower is a cool-season brassica that produces dense white, purple, or green heads called curds. It is more finicky than broccoli but rewards with a mild, nutty flavor.

Ferry County, Washington is in USDA Zone 5b. The average last spring frost is May 10 and the first fall frost is September 24, giving you a growing season of approximately 137 days.

At an elevation of 3,990 feet, Ferry County receives approximately 18.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Cauliflower to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Cauliflower successfully. Mulch heavily to conserve soil moisture.

Ferry County, WA (Zone 5b) Short season
137 days
Last Spring Frost May 10
137 growing days
First Fall Frost September 24

Ferry County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (17 days to spare)
Start indoors: Mar 28 Transplant: May 2 🍅 Harvest: Jun 27 – Aug 29
Recommended (50%) ✓ Fits season (18 days to spare)
Start indoors: Apr 5 Transplant: May 10 🍅 Harvest: Jul 5 – Sep 6
Safe Start (90%) ✓ Fits season (17 days to spare)
Start indoors: Apr 24 Transplant: May 29 🍅 Harvest: Jul 24 – Sep 25

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 Ferry County

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

Soil pH

Your soil pH (5.6โ€“6.4) overlaps with Cauliflower's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

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

Drainage

Cauliflower is a heavy drinker but your soil drains very quickly. Mulch heavily and consider drip irrigation.

Organic Matter

Organic matter is excellent (4.6%) โ€” Cauliflower will thrive.

How to Plant Cauliflower

1"
Planting Depth
15"
Between Plants
24"
Between Rows

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

Succession Planting Cauliflower

2
successive plantings in your 137-day season

Sow every 6.3 weeks. Last sowing by Jun 16 to harvest before frost.

For a dedicated fall crop, sow by Jul 16.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.6″/week
You supply
0.7″/week
Watering frequency 2-3 times/week
Season total 905 gal / 100 sq ft
Cauliflower needs ~1,008 GDD — county provides 1,781 GDD Excellent fit

Cauliflower Planting Timeline โ€” Ferry County, WA

Cauliflower Planting Calendar

Activity When Date Range
Start Indoors April 5 Apr 5 โ€“ Apr 19
Transplant Outdoors May 10 May 10 โ€“ May 24
Direct Sow April 26 Apr 26 โ€“ May 17
Fall Sowing July 16 Jul 16 โ€“ Jul 30
Harvest July 5 Jul 5 โ€“ Sep 6

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 2-3 times/week

๐Ÿ“… Days to Maturity

55โ€“100 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 5b

๐Ÿ“† Growing Season

137 days in Ferry County

Growing Tips for Cauliflower in Ferry County

Direct sow Cauliflower outdoors after May 10 in Ferry County when soil has warmed and frost danger has passed.

Common pests for Cauliflower in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

Ferry County receives only 18" of rain annually. Cauliflower needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Start seeds indoors 6 weeks before transplanting. Blanch white varieties by tying outer leaves over the head. Provide consistent moisture and avoid temperature extremes.

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Strawberries

Level Up Your Garden

Frequently Asked Questions

When should I plant Cauliflower in Ferry County, WA?

Ferry County is in Zone 5b with an average last frost of May 10. Plan your Cauliflower planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Ferry County, WA?

Ferry County, Washington is in USDA Hardiness Zone 5b. The average last spring frost is May 10 and first fall frost is September 24.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Ferry County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.

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