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When to Plant Mitsuba in Guadalupe County, TX

Guadalupe County, Texas Zone 9a August

August to-do list for Guadalupe County, Texas

A quick August briefing for Guadalupe County, Texas gardeners — what's urgent, what's next, and what can wait.

Avg. last frost March 7
Avg. first frost November 21
Soil temp (4") 81°F
Watering Low
Pest pressure High
Daylight 13.1 hrs
September will be here before you know it — start on
  • Fall sowing: mitsuba

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Mitsuba (Japanese parsley) is a shade-loving herb with trefoil leaves and a mild celery-parsley flavor. It is essential in Japanese cuisine for soups, salads, and garnishes.

Guadalupe County, Texas is in USDA Zone 9a. The average last spring frost is March 7 and the first fall frost is November 21, giving you a growing season of approximately 259 days.

At an elevation of 3,679 feet, Guadalupe County receives approximately 63 inches of rainfall annually with predominantly clay soil. Summer highs average 93°F, providing good warmth for Mitsuba during the growing season. Clay soil retains moisture well for Mitsuba, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Mitsuba root diseases.

Guadalupe County, TX (Zone 9a) Long season
259 days
Last Spring Frost March 7
259 growing days
First Fall Frost November 21

Guadalupe County Soil Profile

Soil Type

Clay

Soil pH

6.9-8.2

Drainage

Well Drained

Mitsuba Planting Risk Windows

Early Start (70% safe) ✓ Fits season (154 days to spare)
Start indoors: Jan 30 Transplant: Feb 20 🍅 Harvest: Apr 17 – Jun 12
Recommended (50%) ✓ Fits season (154 days to spare)
Start indoors: Feb 7 Transplant: Feb 28 🍅 Harvest: Apr 25 – Jun 20
Safe Start (90%) ✓ Fits season (144 days to spare)
Start indoors: Mar 9 Transplant: Mar 30 🍅 Harvest: May 25 – Jul 20

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 Guadalupe County

How your county's soil matches Mitsuba's growing requirements.

Soil pH

Your soil pH (6.9–8.2) is more alkaline than Mitsuba prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Your clay soil in Guadalupe County is workable for Mitsuba. Add compost annually to improve structure.

Organic Matter

Organic matter is moderate (2.7%). Annual compost additions will help Mitsuba.

How to Plant Mitsuba

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Mitsuba

6
successive plantings in your 259-day season

Sow every 5.7 weeks. Last sowing by Sep 12 to harvest before frost.

For a dedicated fall crop, sow by Sep 26.

Mitsuba Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Mitsuba

Mitsuba needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Mitsuba Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 2.1" 0" ❄️ Dormant
Mar 4.3" 4.4" 0" ✅ Rainfall sufficient
Apr 4.3" 6.5" 0" ✅ Rainfall sufficient
May 4.3" 9.5" 0" ✅ Rainfall sufficient
Jun 4.3" 9.3" 0" ✅ Rainfall sufficient
Jul 4.3" 8" 0" ✅ Rainfall sufficient
Aug 4.3" 7.1" 0" ✅ Rainfall sufficient
Sep 4.3" 6.4" 0" ✅ Rainfall sufficient
Oct 4.3" 4.5" 0" ✅ Rainfall sufficient
Nov 4.3" 1.9" 2.4" 🚿 Regular watering
Dec 1.6" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Guadalupe County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Mitsuba 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.

Mitsuba needs ~1,185 GDD — county provides 5,115 GDD Excellent fit

Mitsuba Planting Timeline — Guadalupe County, TX

Mitsuba Planting Calendar

Activity When Date Range
Start Indoors February 7 Feb 7 – Feb 21
Transplant Outdoors February 28 Feb 28 – Mar 14
Direct Sow February 14 Feb 14 – Mar 7
Harvest April 25 Apr 25 – Jun 20
Fall Sowing September 26 Sep 26 – Oct 10

Plant 0.5" deep · 8" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors Transplant Outdoors Direct Sow
March Transplant Outdoors Direct Sow
April Harvest
May Harvest
June Harvest
July
August
September Fall Sowing
October Fall Sowing
November
December

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 9a

📆 Growing Season

259 days in Guadalupe County

Growing Tips for Mitsuba in Guadalupe County

Direct sow Mitsuba outdoors after March 07 in Guadalupe County when soil has warmed and frost danger has passed.

With Guadalupe County's clay soil (40% clay), work in 3-4 inches of compost before planting Mitsuba. Avoid tilling when soil is wet to prevent compaction.

Common pests for Mitsuba in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow or start indoors in partial shade. Mitsuba prefers cool, moist conditions. Harvest outer stems as needed. Self-sows readily in shaded garden areas.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Mitsuba in Guadalupe County, TX?

Guadalupe County is in Zone 9a with an average last frost of March 7. Plan your Mitsuba planting based on this frost date — see the calendar above for exact timing.

What planting zone is Guadalupe County, TX?

Guadalupe County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is March 7 and first fall frost is November 21.

🌱

Your Guadalupe County Garden Planner — Free

A 22-page printable planner built for Guadalupe 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.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Guadalupe County, TX. Local conditions may vary. Last updated: August 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.