Blog

When to Plant Thai Basil in Coos 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.

Coos County, Oregon is in USDA Zone 8b. The average last spring frost is March 22 and the first fall frost is November 19, giving you a growing season of approximately 242 days.

At an elevation of 96 feet, Coos County receives approximately 38.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89Β°F, providing good warmth for Thai Basil during the growing season.

Coos County, OR (Zone 8b) Long season
242 days
Last Spring Frost March 22
242 growing days
First Fall Frost November 19

Coos County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.8

Drainage

Well Drained

Monthly Watering Guide for Thai Basil

Thai Basil needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Thai Basil Needs Rainfall You Supplement Action
Jan β€” 5.5" 0" ❄️ Dormant
Feb β€” 4.5" 0" ❄️ Dormant
Mar 4.3" 4.4" 0" βœ… Rainfall sufficient
Apr 4.3" 3.1" 1.2" πŸ’§ Light watering
May 4.3" 2.3" 2" πŸ’§ Light watering
Jun 4.3" 1.6" 2.7" 🚿 Regular watering
Jul 4.3" 0.6" 3.7" 🚿 Regular watering
Aug 4.3" 0.8" 3.5" 🚿 Regular watering
Sep 4.3" 1.4" 2.9" 🚿 Regular watering
Oct 4.3" 3.3" 1" πŸ’§ Light watering
Nov 4.3" 5.9" 0" βœ… Rainfall sufficient
Dec β€” 5.5" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Coos County). Supplement amounts are based on average rainfall β€” actual needs vary with temperature, soil, and mulching.

Thai Basil Planting Timeline β€” Coos County, OR

Thai Basil Planting Calendar

Activity When Date Range
Start Indoors February 1 Feb 1 – Feb 15
Transplant Outdoors April 5 Apr 5 – Apr 19
Direct Sow March 29 Mar 29 – Apr 19
Harvest May 31 May 31 – Aug 2

Plant 0.5" deep Β· 8" apart Β· Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

β˜€οΈ Sun

Full Sun (6-8+ hours)

πŸ’§ Water

Moderate β€” regular watering

πŸ“… Days to Maturity

50–75 days

πŸ§ͺ Soil pH

Needs 6–7 Β· Your soil: N/A

πŸ—ΊοΈ USDA Zone

Zone 8b

πŸ“† Growing Season

242 days in Coos County

Growing Tips for Coos 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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

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

Coos County is in Zone 8b with an average last frost of March 22. Plan your Thai Basil planting based on this frost date β€” see the calendar above for exact timing.

What planting zone is Coos County, OR?

Coos County, Oregon is in USDA Hardiness Zone 8b. The average last spring frost is March 22 and first fall frost is November 19.

🌱

Plan Your Garden with Confidence

Get our free Garden Planner β€” designed to help Coos County gardeners in Zone 8b 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 Coos County, OR. Local conditions may vary. Last updated: April 2026.