When to plant Mizuna in Cass County, IL
Aim to plant Mizuna in Cass County on or after April 1; the window stays open through April 22. Cass County's 184-day frost-free season gives you enough for a full main crop and a short fall succession. A second sowing from August 7 to August 21 extends the harvest into fall.
When to Plant Mizuna in Cass County, IL
Your August game plan for Cass County, Illinois
We've pulled the most time-sensitive tasks for Cass County, Illinois this August and put them front and centre. Tackle them in order.
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Get mizuna in for a late-season harvest
Fall crops get sweeter with a light frost. Don't be afraid of cool nights.
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.
Cass County, Illinois is in USDA Zone 6a. The average last spring frost is April 15 and the first fall frost is October 16, giving you a growing season of approximately 184 days.
At an elevation of 703 feet, Cass County receives approximately 31.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Mizuna to ensure they mature before fall.
Cass County Soil Profile
Soil Type
Silt Loam
Soil pH
6-7.2
Drainage
Well Drained
Mizuna 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 Cass County
How your county's soil matches Mizuna's growing requirements.
Soil pH
Your soil pH (6.0–7.2) is within Mizuna's preferred range (6.0–7.5).
Soil Texture
The silt loam soil in Cass 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 (4.0%). 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 01 to harvest before frost.
For a dedicated fall crop, sow by Aug 07.
Mizuna Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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 | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.4" | 0" | ❄️ Dormant |
| Mar | — | 2.3" | 0" | ❄️ Dormant |
| Apr | 4.3" | 2.8" | 1.5" | 💧 Light watering |
| May | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Jun | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Jul | 4.3" | 3.3" | 1" | 💧 Light watering |
| Aug | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Sep | 4.3" | 3.3" | 1" | 💧 Light watering |
| Oct | 4.3" | 2.6" | 1.7" | 💧 Light watering |
| Nov | — | 2" | 0" | ❄️ Dormant |
| Dec | — | 1.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Cass 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 — Cass County, IL
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 7 | Aug 7 – Aug 21 |
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 · 1-2 times/week
📅 Days to Maturity
30–45 days
🧪 Soil pH
Needs 6–7.5 · Your soil: ideal
🗺️ USDA Zone
Zone 6a
📆 Growing Season
184 days in Cass County
Growing Tips for Mizuna in Cass County
Direct sow Mizuna outdoors after April 15 in Cass County when soil has warmed and frost danger has passed.
Your generous 184.0-day season in Cass 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 Cass County, IL?
Cass 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 Cass County, IL?
Cass County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 15 and first fall frost is October 16.
When should I plant Mizuna in Cass County, IL?
In Cass County, IL, plant Mizuna after the last frost (around April 15) and before the first frost (around October 16). Best results when soil holds above 50°F.
What growing zone is Cass County, IL for Mizuna?
Cass County sits in USDA Zone 6a. Mizuna grows reliably in zones 3a through 11b, so it's a good fit here.
Can Mizuna grow in Cass County's climate?
Yes — Mizuna grows well in Cass County's temperate climate. Cass County averages a 184-day frost-free season, with last frost around April 15 and first frost around October 16.
Your Cass County Garden Planner — Free
A 22-page printable planner built for Cass 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.