When to Plant Mizuna in San Jacinto County, TX
May in the garden — San Jacinto County, Texas
Welcome to May in Zone 9a. These are the moves that will have the biggest impact on your growing season.
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.
San Jacinto County, Texas is in USDA Zone 9a. The average last spring frost is February 18 and the first fall frost is December 1, giving you a growing season of approximately 286 days.
At an elevation of 6 feet, San Jacinto County receives approximately 71.3 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 94°F, providing good warmth for Mizuna during the growing season. Sandy soil warms quickly in spring — great for early planting — but Mizuna will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Mizuna root diseases.
San Jacinto County Soil Profile
Soil Type
Sandy Loam
Soil pH
5.3-6.7
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 San Jacinto County
How your county's soil matches Mizuna's growing requirements.
Soil pH
Your soil pH (5.3–6.7) overlaps with Mizuna's range (6.0–7.5), though not a perfect match.
Soil Texture
Sandy soil in San Jacinto County warms quickly in spring but drains fast. Mizuna will need more frequent watering and regular compost additions to retain nutrients.
Organic Matter
Organic matter is moderate (2.2%). Annual compost additions will help Mizuna.
How to Plant Mizuna
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Mizuna
Sow every 3.4 weeks. Last sowing by Oct 17 to harvest before frost.
For a dedicated fall crop, sow by Oct 06.
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 | — | 1.7" | 0" | ❄️ Dormant |
| Feb | 4.3" | 2.5" | 1.8" | 💧 Light watering |
| Mar | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Apr | 4.3" | 8.5" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 9.5" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 11.4" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 9.2" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 8" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 6.7" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 5.2" | 0" | ✅ Rainfall sufficient |
| Nov | 4.3" | 2.6" | 1.7" | 💧 Light watering |
| Dec | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
Water needs are for active growing months only (Feb–Dec in San Jacinto 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 — San Jacinto County, TX
Mizuna Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 21 | Jan 21 – Feb 4 |
| Transplant Outdoors | February 18 | Feb 18 – Mar 4 |
| Direct Sow | January 28 | Jan 28 – Feb 18 |
| Harvest | March 25 | Mar 25 – Apr 22 |
| Fall Sowing | October 6 | Oct 6 – Oct 20 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors Direct Sow |
| February | Start Indoors Transplant Outdoors Direct Sow |
| March | Transplant Outdoors Harvest |
| April | Harvest |
| May | — |
| June | — |
| July | — |
| August | — |
| September | — |
| October | Fall Sowing |
| 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 9a
📆 Growing Season
286 days in San Jacinto County
Growing Tips for Mizuna in San Jacinto County
Direct sow Mizuna outdoors after February 18 in San Jacinto County when soil has warmed and frost danger has passed.
Sandy soil in San Jacinto County dries quickly — mulch Mizuna with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
Your generous 287.0-day season in San Jacinto 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 San Jacinto County, TX?
San Jacinto County is in Zone 9a with an average last frost of February 18. Plan your Mizuna planting based on this frost date — see the calendar above for exact timing.
What planting zone is San Jacinto County, TX?
San Jacinto County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 18 and first fall frost is December 1.
Your San Jacinto County Garden Planner — Free
A 24-page printable planner built for San Jacinto County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.