When to Plant Mitsuba in Grant County, WA
Mitsuba (Japanese parsley) is a shade-loving herb with trefoil leaves and a mild celery-parsley flavor. It is essential in Japanese cuisine for soups, salads, and garnishes.
Grant County, Washington is in USDA Zone 7a. 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 91°F, providing good warmth for Mitsuba during the growing season. With low rainfall, drip irrigation is essential for growing Mitsuba successfully. Mulch heavily to conserve soil moisture.
Grant County Soil Profile
Soil Type
Silt Loam
Soil pH
5.6-6.8
Drainage
Well Drained
Monthly Watering Guide for Mitsuba
Mitsuba needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Mitsuba Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 2.7" | 0" | ❄️ Dormant |
| Feb | — | 1.8" | 0" | ❄️ Dormant |
| Mar | — | 2" | 0" | ❄️ Dormant |
| Apr | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| May | 4.3" | 1.1" | 3.2" | 🚿 Regular watering |
| Jun | 4.3" | 0.7" | 3.6" | 🚿 Regular watering |
| Jul | 4.3" | 0.2" | 4.1" | 🚿 Regular watering |
| Aug | 4.3" | 0.4" | 3.9" | 🚿 Regular watering |
| Sep | 4.3" | 0.6" | 3.7" | 🚿 Regular watering |
| Oct | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Nov | — | 2.5" | 0" | ❄️ Dormant |
| Dec | — | 2.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Grant County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Mitsuba Planting Timeline — Grant County, WA
Mitsuba Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 25 | Mar 25 – Apr 8 |
| Transplant Outdoors | April 22 | Apr 22 – May 6 |
| Direct Sow | April 15 | Apr 15 – May 6 |
| Harvest | June 17 | Jun 17 – Aug 12 |
| Fall Sowing | August 1 | Aug 1 – Aug 15 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 7a
📆 Growing Season
164 days in Grant County
Growing Tips for Grant County
Direct sow or start indoors in partial shade. Mitsuba prefers cool, moist conditions. Harvest outer stems as needed. Self-sows readily in shaded garden areas.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Mitsuba in Other Locations
Frequently Asked Questions
When should I plant Mitsuba in Grant County, WA?
Grant County is in Zone 7a with an average last frost of April 29. Plan your Mitsuba planting based on this frost date — see the calendar above for exact timing.
What planting zone is Grant County, WA?
Grant County, Washington is in USDA Hardiness Zone 7a. The average last spring frost is April 29 and first fall frost is October 10.
Your Grant County Garden Planner — Free
A 22-page printable planner built for Grant County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.