When to Plant Mizuna in Lee County, IA
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.
Lee County, Iowa is in USDA Zone 5b. The average last spring frost is April 16 and the first fall frost is October 18, giving you a growing season of approximately 185 days.
At an elevation of 1,393 feet, Lee County receives approximately 36.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Mizuna to ensure they mature before fall.
Lee County Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-7.2
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.
Plant Water Budget
Mizuna Planting Timeline — Lee County, IA
Mizuna Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 12 | Mar 12 – Mar 26 |
| Transplant Outdoors | April 16 | Apr 16 – Apr 30 |
| Direct Sow | April 2 | Apr 2 – Apr 23 |
| Fall Sowing | August 9 | Aug 9 – Aug 23 |
| Harvest | May 21 | May 21 – Jun 18 |
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
Moderate — regular watering
Days to Maturity
30–45 days
Soil pH
6 – 7.5
USDA Zone
Zone 5b
Growing Season
185 days
Growing Tips for Lee County
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
Level Up Your Garden
Mizuna in Other Locations
Frequently Asked Questions
When should I plant Mizuna in Lee County, IA?
Lee County is in Zone 5b with an average last frost of April 16. Plan your Mizuna planting based on this frost date — see the calendar above for exact timing.
What planting zone is Lee County, IA?
Lee County, Iowa is in USDA Hardiness Zone 5b. The average last spring frost is April 16 and first fall frost is October 18.
Plan Your Garden with Confidence
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