When to Plant Lemongrass in Columbia County, OR
Lemongrass is a tropical grass with a strong citrus aroma used extensively in Southeast Asian cuisine. The swollen stem bases are the most flavorful part.
Columbia County, Oregon is in USDA Zone 8a. The average last spring frost is April 14 and the first fall frost is October 29, giving you a growing season of approximately 198 days.
At an elevation of 396 feet, Columbia County receives approximately 46.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Lemongrass during the growing season.
Columbia County Soil Profile
Soil Type
Silt Loam
Soil pH
5.5-6.6
Drainage
Well Drained
Plant Planting Risk Windows
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 Columbia County
How your county's soil matches Lemongrass's growing requirements.
Soil pH
Your soil pH (5.5–6.6) is within Lemongrass's preferred range (5.5–7.5).
Soil Texture
The silt loam soil in Columbia County is excellent for Lemongrass — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.6%) — Lemongrass will thrive.
How to Plant Lemongrass
Succession Planting Lemongrass
Sow every 8.6 weeks. Last sowing by Jul 01 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Lemongrass
Lemongrass needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.
| Month | Lemongrass Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 6.5" | 0" | ❄️ Dormant |
| Feb | — | 4.8" | 0" | ❄️ Dormant |
| Mar | — | 4.9" | 0" | ❄️ Dormant |
| Apr | 6.5" | 3.2" | 3.3" | 🚿 Regular watering |
| May | 6.5" | 2.9" | 3.6" | 🚿 Regular watering |
| Jun | 6.5" | 1.7" | 4.8" | 🚿 Regular watering |
| Jul | 6.5" | 0.7" | 5.8" | 🚿 Regular watering |
| Aug | 6.5" | 0.8" | 5.7" | 🚿 Regular watering |
| Sep | 6.5" | 1.9" | 4.6" | 🚿 Regular watering |
| Oct | 6.5" | 3.9" | 2.6" | 💧 Light watering |
| Nov | — | 7.6" | 0" | ❄️ Dormant |
| Dec | — | 7.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Columbia County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Lemongrass 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" — every day above 50°F 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.
Lemongrass Planting Timeline — Columbia County, OR
Lemongrass Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 24 | Feb 24 – Mar 10 |
| Transplant Outdoors | April 28 | Apr 28 – May 12 |
| Direct Sow | April 21 | Apr 21 – May 12 |
| Harvest | July 14 | Jul 14 – Oct 13 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.5"/week · 1-2 times/week
📅 Days to Maturity
75–120 days
🧪 Soil pH
Needs 5.5–7.5 · Your soil: ideal
🗺️ USDA Zone
Zone 8a
📆 Growing Season
198 days in Columbia County
Growing Tips for Lemongrass in Columbia County
Direct sow Lemongrass outdoors after April 14 in Columbia County when soil has warmed and frost danger has passed.
Common pests for Lemongrass in this region include corn earworm and corn borers. Use row covers early in the season and inspect plants weekly.
General growing tips
Start from divisions or store-bought stalks rooted in water. Grow in rich, moist soil with full sun. In cold climates, grow in containers and overwinter indoors.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Lemongrass in Other Locations
Frequently Asked Questions
When should I plant Lemongrass in Columbia County, OR?
Columbia County is in Zone 8a with an average last frost of April 14. Plan your Lemongrass planting based on this frost date — see the calendar above for exact timing.
What planting zone is Columbia County, OR?
Columbia County, Oregon is in USDA Hardiness Zone 8a. The average last spring frost is April 14 and first fall frost is October 29.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Columbia County gardeners in Zone 8a organize planting dates, track what's growing, and never miss a planting window.
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