When to Plant Mizuna in Shelby County, AL
Your April planting checklist for Shelby County, Alabama
Here's what deserves your attention in Shelby County, Alabama this month. Everything below is tailored to Zone 7b and timed around your local frost dates.
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Start mizuna indoors
These need a head start before your last frost (March 26). Sow into cells now so you're ready to transplant in a few weeks.
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Collect mizuna at their peak
This is the payoff month. Bring a basket, bring a friend, and get into the beds.
Get ahead of May
- 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.
Shelby County, Alabama is in USDA Zone 7b. The average last spring frost is March 26 and the first fall frost is November 5, giving you a growing season of approximately 224 days.
At an elevation of 324 feet, Shelby County receives approximately 48.8 inches of rainfall annually with predominantly clay loam soil. Summer highs average 90°F, providing good warmth for Mizuna during the growing season. Clay soil retains moisture well for Mizuna, but amend with compost to improve drainage and prevent root rot.
Shelby County Soil Profile
Soil Type
Clay Loam
Soil pH
5.6-6.5
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 Shelby County
How your county's soil matches Mizuna's growing requirements.
Soil pH
Your soil pH (5.6–6.5) overlaps with Mizuna's range (6.0–7.5), though not a perfect match.
Soil Texture
The clay loam soil in Shelby County is excellent for Mizuna — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.8%). 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 21 to harvest before frost.
For a dedicated fall crop, sow by Aug 27.
Plant 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 | — | 4.5" | 0" | ❄️ Dormant |
| Feb | — | 4.5" | 0" | ❄️ Dormant |
| Mar | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Apr | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| May | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Jun | 4.3" | 4" | 0.3" | 💧 Light watering |
| Jul | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Sep | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Oct | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Nov | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Dec | — | 3.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Shelby 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 — Shelby County, AL
Mizuna Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 19 | Feb 19 – Mar 5 |
| Transplant Outdoors | March 26 | Mar 26 – Apr 9 |
| Direct Sow | March 12 | Mar 12 – Apr 2 |
| Harvest | April 30 | Apr 30 – May 28 |
| Fall Sowing | August 27 | Aug 27 – Sep 10 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Transplant Outdoors Direct Sow |
| April | Transplant Outdoors Direct Sow Harvest |
| May | Harvest |
| June | — |
| July | — |
| August | Fall Sowing |
| September | Fall Sowing |
| 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: acceptable
🗺️ USDA Zone
Zone 7b
📆 Growing Season
224 days in Shelby County
Growing Tips for Mizuna in Shelby County
Direct sow Mizuna outdoors after March 26 in Shelby County when soil has warmed and frost danger has passed.
With Shelby County's clay soil (33% clay), work in 3-4 inches of compost before planting Mizuna. Avoid tilling when soil is wet to prevent compaction.
Your generous 224.0-day season in Shelby 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 Shelby County, AL?
Shelby County is in Zone 7b with an average last frost of March 26. Plan your Mizuna planting based on this frost date — see the calendar above for exact timing.
What planting zone is Shelby County, AL?
Shelby County, Alabama is in USDA Hardiness Zone 7b. The average last spring frost is March 26 and first fall frost is November 5.
Your Shelby County Garden Planner — Free
A 24-page printable planner built for Shelby County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.