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When to Plant Radish in Pend Oreille County, WA

Radishes are one of the fastest-growing vegetables, with some varieties ready in under a month. They come in round, elongated, and large winter types.

Pend Oreille County, Washington is in USDA Zone 5b. The average last spring frost is May 10 and the first fall frost is September 23, giving you a growing season of approximately 136 days.

At an elevation of 3,807 feet, Pend Oreille County receives approximately 13.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86ยฐF, providing good warmth for Radish during the growing season. With low rainfall, drip irrigation is essential for growing Radish successfully. Mulch heavily to conserve soil moisture.

Pend Oreille County, WA (Zone 5b) Short season
136 days
Last Spring Frost May 10
136 growing days
First Fall Frost September 23

Pend Oreille County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (88 days to spare)
Transplant: May 1 🍅 Harvest: May 29 – Jun 19
Recommended (50%) ✓ Fits season (87 days to spare)
Transplant: May 10 🍅 Harvest: Jun 7 – Jun 28
Safe Start (90%) ✓ Fits season (85 days to spare)
Transplant: May 31 🍅 Harvest: Jun 28 – Jul 19

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 Pend Oreille County

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

Soil pH

Your soil pH (5.3โ€“6.6) is more acidic than Radish prefers (6.0โ€“7.0). Add garden lime to raise pH.

Soil Texture

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

Drainage

Drainage is adequate for Radish.

Organic Matter

Organic matter is excellent (5.0%) โ€” Radish will thrive.

How to Plant Radish

0.5"
Planting Depth
2"
Between Plants
6"
Between Rows

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

Succession Planting Radish

7
successive plantings in your 136-day season

Sow every 2.4 weeks. Last sowing by Aug 19 to harvest before frost.

For a dedicated fall crop, sow by Jul 15.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.4″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 293 gal / 100 sq ft

Monthly Watering Guide for Radish

Radish needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Radish Needs Rainfall You Supplement Action
Jan โ€” 1.8" 0" โ„๏ธ Dormant
Feb โ€” 1.4" 0" โ„๏ธ Dormant
Mar โ€” 1.3" 0" โ„๏ธ Dormant
Apr โ€” 0.9" 0" โ„๏ธ Dormant
May 2.2" 0.8" 1.4" ๐Ÿšฟ Regular watering
Jun 2.2" 0.5" 1.7" ๐Ÿšฟ Regular watering
Jul 2.2" 0.2" 2" ๐Ÿšฟ Regular watering
Aug 2.2" 0.2" 2" ๐Ÿšฟ Regular watering
Sep 2.2" 0.6" 1.6" ๐Ÿšฟ Regular watering
Oct โ€” 1.3" 0" โ„๏ธ Dormant
Nov โ€” 2.1" 0" โ„๏ธ Dormant
Dec โ€” 1.9" 0" โ„๏ธ Dormant

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

Radish 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.

Radish needs ~413 GDD — county provides 1,972 GDD Excellent fit

Radish Planting Timeline โ€” Pend Oreille County, WA

Radish Planting Calendar

Activity When Date Range
Direct Sow April 26 Apr 26 โ€“ May 17
Harvest May 24 May 24 โ€“ Jun 14
Fall Sowing July 15 Jul 15 โ€“ Jul 29

Plant 0.5" deep ยท 2" apart ยท Rows 6" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.5"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

22โ€“35 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 5b

๐Ÿ“† Growing Season

136 days in Pend Oreille County

Growing Tips for Radish in Pend Oreille County

Direct sow Radish outdoors after May 10 in Pend Oreille County when soil has warmed and frost danger has passed.

Your generous 136.0-day season in Pend Oreille County allows multiple plantings of Radish. Sow every 11.0 days for continuous harvest.

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

General growing tips

Direct sow every 1-2 weeks for continuous harvest. Do not transplant. Harvest spring radishes promptly to prevent them from becoming pithy and hot.

Companion Planting

Good Companions

Avoid Planting Near

  • Hyssop

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Radish in Pend Oreille County, WA?

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

What planting zone is Pend Oreille County, WA?

Pend Oreille County, Washington is in USDA Hardiness Zone 5b. The average last spring frost is May 10 and first fall frost is September 23.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Pend Oreille 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 Pend Oreille County, WA. Local conditions may vary. Last updated: April 2026.