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When to Plant Rue in Grant County, WA

Rue is a bitter, aromatic perennial herb with bluish-green foliage used historically in medicine and as a pest deterrent. Handle with care as its sap can cause skin irritation.

Grant County, Washington is in USDA Zone 6b. The average last spring frost is April 29 and the first fall frost is October 10, giving you a growing season of approximately 164 days.

At an elevation of 3,122 feet, Grant County receives approximately 17.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91ยฐF, providing good warmth for Rue during the growing season. With low rainfall, drip irrigation is essential for growing Rue successfully. Mulch heavily to conserve soil moisture.

Grant County, WA (Zone 6b) Moderate season
164 days
Last Spring Frost April 29
164 growing days
First Fall Frost October 10

Grant County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (30 days to spare)
Transplant: Apr 21 🍅 Harvest: Jun 30 – Sep 1
Recommended (50%) ✓ Fits season (24 days to spare)
Transplant: May 6 🍅 Harvest: Jul 15 – Sep 16
Safe Start (90%) ✓ Fits season (28 days to spare)
Transplant: May 26 🍅 Harvest: Aug 4 – Oct 6

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.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.5″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 72 gal / 100 sq ft
Rue needs ~1,460 GDD — county provides 2,993 GDD Excellent fit

Rue Planting Timeline โ€” Grant County, WA

Rue Planting Calendar

Activity When Date Range
Transplant Outdoors May 6 May 6 โ€“ May 20
Harvest July 15 Jul 15 โ€“ Sep 16

Plant 0.5" deep ยท 8" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May Transplant Outdoors
June โ€”
July Harvest
August Harvest
September Harvest
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Low โ€” drought tolerant

Days to Maturity

70โ€“90 days

Soil pH

6 โ€“ 7.5

USDA Zone

Zone 6b

Growing Season

164 days

Growing Tips for Grant County

Start seeds indoors or direct sow. Plant in well-drained soil. Wear gloves when handling as sap can cause phytophotodermatitis. Prune in early spring.

Companion Planting

Good Companions

Avoid Planting Near

  • Basil
  • Sage

Level Up Your Garden

Frequently Asked Questions

When should I plant Rue in Grant County, WA?

Grant County is in Zone 6b with an average last frost of April 29. Plan your Rue planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Grant County, WA?

Grant County, Washington is in USDA Hardiness Zone 6b. The average last spring frost is April 29 and first fall frost is October 10.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Grant County gardeners in Zone 6b 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 Grant County, WA. Local conditions may vary. Last updated: April 2026.