Blog

When to Plant Thai Basil in Deschutes County, OR

Thai basil has a distinctive anise-licorice flavor with sturdy purple stems and small leaves. It is essential in Thai, Vietnamese, and other Southeast Asian cuisines.

Deschutes County, Oregon is in USDA Zone 6a. The average last spring frost is June 15 and the first fall frost is September 13, giving you a growing season of approximately 90 days.

At an elevation of 221 feet, Deschutes County receives approximately 54.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81ยฐF, so choose short-season varieties of Thai Basil to ensure they mature before fall. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Thai Basil root diseases.

Deschutes County, OR (Zone 6a) Very short season
90 days
Last Spring Frost June 15
90 growing days
First Fall Frost September 13

Deschutes County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Apr 15 Transplant: Jun 17 🍅 Harvest: Aug 12 – Oct 14
Recommended (50%) ✗ May not fit
Start indoors: Apr 27 Transplant: Jun 29 🍅 Harvest: Aug 24 – Oct 26
Safe Start (90%) ✗ May not fit
Start indoors: May 8 Transplant: Jul 10 🍅 Harvest: Sep 4 – Nov 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
1.0″/week
Rainfall provides
2.6″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Thai Basil needs ~672 GDD — county provides 967 GDD Excellent fit

Thai Basil Planting Timeline โ€” Deschutes County, OR

Thai Basil Planting Calendar

Activity When Date Range
Start Indoors April 27 Apr 27 โ€“ May 11
Transplant Outdoors June 29 Jun 29 โ€“ Jul 13
Direct Sow June 22 Jun 22 โ€“ Jul 13
Harvest August 24 Aug 24 โ€“ Oct 26

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

50โ€“75 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 6a

Growing Season

90 days

Growing Tips for Deschutes County

Start seeds indoors or direct sow after last frost. Thai basil holds up better to heat in cooking than sweet basil. Pinch flowers to prolong leaf production.

Companion Planting

Good Companions

Avoid Planting Near

  • Rue
  • Sage

Level Up Your Garden

Frequently Asked Questions

When should I plant Thai Basil in Deschutes County, OR?

Deschutes County is in Zone 6a with an average last frost of June 15. Plan your Thai Basil planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Deschutes County, OR?

Deschutes County, Oregon is in USDA Hardiness Zone 6a. The average last spring frost is June 15 and first fall frost is September 13.

๐ŸŒฑ

Plan Your Garden with Confidence

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