Blog

When to Plant Mitsuba in Washakie County, WY

Washakie County, Wyoming Zone 4b May

Your May planting checklist for Washakie County, Wyoming

Your Washakie County, Wyoming garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.

Avg. last frost May 10
Avg. first frost October 2
Soil temp (4") 35°F
Watering High
Pest pressure Low
Daylight 14.5 hrs
  1. Move mitsuba from tray to bed

    Your last frost (May 10) has passed. These warm-season crops can handle outdoor soil now.

  2. Scatter mitsuba into prepared beds

    These tolerate cool soil, so you're not gambling by sowing now.

Get ahead of June
  • Starting indoors: mitsuba
  • First harvests: mitsuba

Instant PDF download. No spam, unsubscribe any time.

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.

Washakie County, Wyoming is in USDA Zone 4b. The average last spring frost is May 10 and the first fall frost is October 2, giving you a growing season of approximately 145 days.

At an elevation of 6,932 feet, Washakie County receives approximately 13.1 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Mitsuba to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Mitsuba successfully. Mulch heavily to conserve soil moisture.

Washakie County, WY (Zone 4b) Short season
145 days
Last Spring Frost May 10
145 growing days
First Fall Frost October 2
Share this guide:

Washakie County Soil Profile

Soil Type

Loam

Soil pH

6.2-8.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (38 days to spare)
Start indoors: Mar 22 Transplant: Apr 26 🍅 Harvest: Jun 21 – Aug 16
Recommended (50%) ✓ Fits season (40 days to spare)
Start indoors: Mar 29 Transplant: May 3 🍅 Harvest: Jun 28 – Aug 23
Safe Start (90%) ✓ Fits season (45 days to spare)
Start indoors: Apr 7 Transplant: May 12 🍅 Harvest: Jul 7 – Sep 1

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 Washakie County

How your county's soil matches Mitsuba's growing requirements.

Soil pH

Your soil pH (6.2–8.2) is more alkaline than Mitsuba prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Washakie County is excellent for Mitsuba — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.6%). Annual compost additions will help Mitsuba.

How to Plant Mitsuba

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Succession Planting Mitsuba

3
successive plantings in your 145-day season

Sow every 5.7 weeks. Last sowing by Jul 24 to harvest before frost.

For a dedicated fall crop, sow by Jul 10.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.4″/week
You supply
0.7″/week
Watering frequency 2-3 times/week
Season total 961 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — consider drought-tolerant varieties and mulching

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 0.8" 0" ❄️ Dormant
Feb 0.7" 0" ❄️ Dormant
Mar 1.2" 0" ❄️ Dormant
Apr 1.5" 0" ❄️ Dormant
May 4.3" 1.6" 2.7" 🚿 Regular watering
Jun 4.3" 0.9" 3.4" 🚿 Regular watering
Jul 4.3" 1.1" 3.2" 🚿 Regular watering
Aug 4.3" 1.3" 3" 🚿 Regular watering
Sep 4.3" 1.1" 3.2" 🚿 Regular watering
Oct 4.3" 1.2" 3.1" 🚿 Regular watering
Nov 0.8" 0" ❄️ Dormant
Dec 0.8" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Washakie County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Mitsuba 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.

Mitsuba needs ~780 GDD — county provides 1,885 GDD Excellent fit

Mitsuba Planting Timeline — Washakie County, WY

Mitsuba Planting Calendar

Activity When Date Range
Start Indoors March 29 Mar 29 – Apr 12
Transplant Outdoors May 3 May 3 – May 17
Direct Sow May 3 May 3 – May 24
Harvest June 28 Jun 28 – Aug 23
Fall Sowing July 10 Jul 10 – Jul 24

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Start Indoors
May Transplant Outdoors Direct Sow
June Harvest
July Fall Sowing Harvest
August Harvest
September
October
November
December
Share this guide:

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · 2-3 times/week

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 4b

📆 Growing Season

145 days in Washakie County

Growing Tips for Mitsuba in Washakie County

Direct sow Mitsuba outdoors after May 10 in Washakie County when soil has warmed and frost danger has passed.

Common pests for Mitsuba in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.

Washakie County receives only 13" of rain annually. Mitsuba needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

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 →

Frequently Asked Questions

When should I plant Mitsuba in Washakie County, WY?

Washakie County is in Zone 4b with an average last frost of May 10. Plan your Mitsuba planting based on this frost date — see the calendar above for exact timing.

What planting zone is Washakie County, WY?

Washakie County, Wyoming is in USDA Hardiness Zone 4b. The average last spring frost is May 10 and first fall frost is October 2.

🌱

Your Washakie County Garden Planner — Free

A 24-page printable planner built for Washakie County (Zone 4b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Washakie County, WY. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.