When to Plant Mizuna in Skamania County, WA
Top priorities for Skamania County, Washington gardeners in May
May is a pivotal month for Skamania County, Washington gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Begin indoor sowing: mizuna
You're about 21 weeks out from your last frost — the perfect window to get these germinating indoors.
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It's harvest week for mizuna
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
June prep starts now
- First harvests: mizuna
Mizuna is a mild-flavored Japanese mustard green with feathery, deeply serrated leaves. It is fast-growing and makes an excellent addition to salads and stir-fries.
Skamania County, Washington is in USDA Zone 8a. The average last spring frost is April 18 and the first fall frost is October 19, giving you a growing season of approximately 184 days.
At an elevation of 16 feet, Skamania County receives approximately 43 inches of rainfall annually with predominantly silt loam soil. Summer highs average 79°F, so choose short-season varieties of Mizuna to ensure they mature before fall.
Skamania County Soil Profile
Soil Type
Silt Loam
Soil pH
5.6-6.2
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 Skamania County
How your county's soil matches Mizuna's growing requirements.
Soil pH
Your soil pH (5.6–6.2) is more acidic than Mizuna prefers (6.0–7.5). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Skamania County is excellent for Mizuna — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.0%) — Mizuna will thrive.
How to Plant Mizuna
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Mizuna
Sow every 3.4 weeks. Last sowing by Sep 04 to harvest before frost.
For a dedicated fall crop, sow by Aug 10.
Plant Water Budget
Monthly Watering Guide for Mizuna
Mizuna needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Mizuna Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 6.5" | 0" | ❄️ Dormant |
| Feb | — | 4.3" | 0" | ❄️ Dormant |
| Mar | — | 3.8" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| May | 4.3" | 2.1" | 2.2" | 🚿 Regular watering |
| Jun | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Jul | 4.3" | 0.7" | 3.6" | 🚿 Regular watering |
| Aug | 4.3" | 0.7" | 3.6" | 🚿 Regular watering |
| Sep | 4.3" | 1.8" | 2.5" | 🚿 Regular watering |
| Oct | 4.3" | 3.3" | 1" | 💧 Light watering |
| Nov | — | 7.4" | 0" | ❄️ Dormant |
| Dec | — | 7.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Skamania County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Mizuna 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.
Mizuna Planting Timeline — Skamania County, WA
Mizuna Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 14 | Mar 14 – Mar 28 |
| Transplant Outdoors | April 18 | Apr 18 – May 2 |
| Direct Sow | April 4 | Apr 4 – Apr 25 |
| Harvest | May 23 | May 23 – Jun 20 |
| Fall Sowing | August 10 | Aug 10 – Aug 24 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Harvest |
| June | Harvest |
| July | — |
| August | Fall Sowing |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
30–45 days
🧪 Soil pH
Needs 6–7.5 · Your soil: too_acidic
🗺️ USDA Zone
Zone 8a
📆 Growing Season
184 days in Skamania County
Growing Tips for Mizuna in Skamania County
Direct sow Mizuna outdoors after April 18 in Skamania County when soil has warmed and frost danger has passed.
Your generous 184.0-day season in Skamania County allows multiple plantings of Mizuna. Sow every 15.0 days for continuous harvest.
Common pests for Mizuna in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow in spring or fall. Harvest outer leaves as needed for a cut-and-come-again approach. Mizuna is one of the most cold-tolerant Asian greens.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Mizuna in Other Locations
Frequently Asked Questions
When should I plant Mizuna in Skamania County, WA?
Skamania County is in Zone 8a with an average last frost of April 18. Plan your Mizuna planting based on this frost date — see the calendar above for exact timing.
What planting zone is Skamania County, WA?
Skamania County, Washington is in USDA Hardiness Zone 8a. The average last spring frost is April 18 and first fall frost is October 19.
Your Skamania County Garden Planner — Free
A 24-page printable planner built for Skamania County (Zone 8a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.