When to Plant Microgreens in Cowlitz County, WA
Microgreens are young seedlings of vegetables and herbs harvested at the cotyledon or first true leaf stage. They pack concentrated flavors and nutrients in a tiny package.
Cowlitz County, Washington is in USDA Zone 8b. The average last spring frost is April 15 and the first fall frost is October 29, giving you a growing season of approximately 197 days.
At an elevation of 268 feet, Cowlitz County receives approximately 47.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Microgreens during the growing season.
Cowlitz County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-6.5
Drainage
Well Drained
Monthly Watering Guide for Microgreens
Microgreens needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Microgreens Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 7.2" | 0" | ❄️ Dormant |
| Feb | — | 4.6" | 0" | ❄️ Dormant |
| Mar | — | 5.1" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| May | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| Jun | 4.3" | 2" | 2.3" | 🚿 Regular watering |
| Jul | 4.3" | 0.8" | 3.5" | 🚿 Regular watering |
| Aug | 4.3" | 0.9" | 3.4" | 🚿 Regular watering |
| Sep | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
| Oct | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Nov | — | 7.6" | 0" | ❄️ Dormant |
| Dec | — | 7.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Cowlitz County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Microgreens Planting Timeline — Cowlitz County, WA
Microgreens Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 11 | Mar 11 – Mar 25 |
| Transplant Outdoors | April 15 | Apr 15 – Apr 29 |
| Direct Sow | April 1 | Apr 1 – Apr 22 |
| Harvest | April 22 | Apr 22 – May 20 |
| Fall Sowing | August 20 | Aug 20 – Sep 3 |
Plant 0.5" deep · 2" apart · Rows 6" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow Harvest |
| May | Harvest |
| June | — |
| July | — |
| August | Fall Sowing |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
7–21 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 8b
📆 Growing Season
197 days in Cowlitz County
Growing Tips for Cowlitz County
Sow seeds densely on shallow trays of moist growing medium. Cover until germination, then provide light. Harvest with scissors when 1-3 inches tall. Grow year-round indoors.
Microgreens in Other Locations
Frequently Asked Questions
When should I plant Microgreens in Cowlitz County, WA?
Cowlitz County is in Zone 8b with an average last frost of April 15. Plan your Microgreens planting based on this frost date — see the calendar above for exact timing.
What planting zone is Cowlitz County, WA?
Cowlitz County, Washington is in USDA Hardiness Zone 8b. The average last spring frost is April 15 and first fall frost is October 29.
Your Cowlitz County Garden Planner — Free
A 22-page printable planner built for Cowlitz County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.