When to Plant Mizuna in Lewis County, MO
Lewis County, Missouri gardeners: here's your May plan
If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.
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Time to start mizuna inside
Starting these indoors now means sturdy transplants ready the moment your soil warms up.
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Bring in the mizuna
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
A few tasks this May that'll pay off in June
- 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.
Lewis County, Missouri is in USDA Zone 6a. The average last spring frost is April 15 and the first fall frost is October 17, giving you a growing season of approximately 185 days.
At an elevation of 945 feet, Lewis County receives approximately 31.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Mizuna during the growing season.
Lewis County Soil Profile
Soil Type
Silt Loam
Soil pH
5.3-6.8
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 Lewis County
How your county's soil matches Mizuna's growing requirements.
Soil pH
Your soil pH (5.3–6.8) overlaps with Mizuna's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Lewis County is excellent for Mizuna — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Mizuna.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Mizuna.
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 02 to harvest before frost.
For a dedicated fall crop, sow by Aug 08.
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 | — | 1.1" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.4" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.3" | 1" | 💧 Light watering |
| May | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Jun | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Jul | 4.3" | 3.1" | 1.2" | 💧 Light watering |
| Aug | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Sep | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| Oct | 4.3" | 2.2" | 2.1" | 💧 Light watering |
| Nov | — | 2.1" | 0" | ❄️ Dormant |
| Dec | — | 1.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Lewis 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 — Lewis County, MO
Mizuna 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 | May 20 | May 20 – Jun 17 |
| Fall Sowing | August 8 | Aug 8 – Aug 22 |
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 | Harvest |
| June | Harvest |
| July | — |
| August | Fall Sowing |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · Natural rainfall sufficient
📅 Days to Maturity
30–45 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 6a
📆 Growing Season
185 days in Lewis County
Growing Tips for Mizuna in Lewis County
Direct sow Mizuna outdoors after April 15 in Lewis County when soil has warmed and frost danger has passed.
Your generous 185.0-day season in Lewis 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 Lewis County, MO?
Lewis County is in Zone 6a with an average last frost of April 15. Plan your Mizuna planting based on this frost date — see the calendar above for exact timing.
What planting zone is Lewis County, MO?
Lewis County, Missouri is in USDA Hardiness Zone 6a. The average last spring frost is April 15 and first fall frost is October 17.
Your Lewis County Garden Planner — Free
A 24-page printable planner built for Lewis County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.