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When to Plant Shiso in Val Verde County, TX

Shiso (perilla) is a fragrant Japanese herb with large, ruffled leaves in green or purple varieties. It has a unique flavor combining mint, basil, and anise.

Val Verde County, Texas is in USDA Zone 8a. The average last spring frost is February 17 and the first fall frost is December 7, giving you a growing season of approximately 293 days.

At an elevation of 3,979 feet, Val Verde County receives approximately 53.1 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 98ยฐF, so Shiso may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Shiso will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Shiso root diseases.

Val Verde County, TX (Zone 8a) Year-round
293 days
Last Spring Frost February 17
293 growing days
First Fall Frost December 7

Val Verde County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.7-8.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (166 days to spare)
Start indoors: Dec 25 Transplant: Feb 26 🍅 Harvest: Apr 23 – Jun 18
Recommended (50%) ✓ Fits season (167 days to spare)
Start indoors: Dec 30 Transplant: Mar 3 🍅 Harvest: Apr 28 – Jun 23
Safe Start (90%) ✓ Fits season (161 days to spare)
Start indoors: Jan 19 Transplant: Mar 23 🍅 Harvest: May 18 – Jul 13

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 Val Verde County

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

Soil pH

Your soil pH (7.7โ€“8.1) is more alkaline than Shiso prefers (5.5โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Val Verde County warms quickly in spring but drains fast. Shiso will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is low (0.9%). Add 2-3 inches of compost before planting Shiso.

How to Plant Shiso

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

Succession Planting Shiso

7
successive plantings in your 293-day season

Sow every 5.7 weeks. Last sowing by Sep 28 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 758 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Shiso

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

Month Shiso Needs Rainfall You Supplement Action
Jan โ€” 3.8" 0" โ„๏ธ Dormant
Feb 4.3" 3.1" 1.2" ๐Ÿ’ง Light watering
Mar 4.3" 2.8" 1.5" ๐Ÿ’ง Light watering
Apr 4.3" 1.7" 2.6" ๐Ÿšฟ Regular watering
May 4.3" 1.1" 3.2" ๐Ÿšฟ Regular watering
Jun 4.3" 1.7" 2.6" ๐Ÿšฟ Regular watering
Jul 4.3" 9.6" 0" โœ… Rainfall sufficient
Aug 4.3" 11.5" 0" โœ… Rainfall sufficient
Sep 4.3" 6.2" 0" โœ… Rainfall sufficient
Oct 4.3" 4.3" 0" โœ… Rainfall sufficient
Nov 4.3" 3.3" 1" ๐Ÿ’ง Light watering
Dec 4.3" 4" 0.3" ๐Ÿ’ง Light watering

Water needs are for active growing months only (Febโ€“Dec in Val Verde County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Shiso 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" โ€” every day above 50ยฐF 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.

Shiso needs ~1,410 GDD — county provides 6,909 GDD Excellent fit

Shiso Planting Timeline โ€” Val Verde County, TX

Shiso Planting Calendar

Activity When Date Range
Start Indoors December 30 Dec 30 โ€“ Jan 13
Transplant Outdoors March 3 Mar 3 โ€“ Mar 17
Direct Sow February 24 Feb 24 โ€“ Mar 17
Harvest April 28 Apr 28 โ€“ Jun 23

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

50โ€“70 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 8a

๐Ÿ“† Growing Season

293 days in Val Verde County

Growing Tips for Shiso in Val Verde County

Direct sow Shiso outdoors after February 17 in Val Verde County when soil has warmed and frost danger has passed.

Sandy soil in Val Verde County dries quickly โ€” mulch Shiso with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 98ยฐF in Val Verde County, provide afternoon shade for Shiso and water deeply in the morning.

General growing tips

Direct sow after last frost or start indoors. Both green and red varieties are available. Pinch tips to encourage bushiness. Self-sows prolifically; deadhead to control.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Shiso in Val Verde County, TX?

Val Verde County is in Zone 8a with an average last frost of February 17. Plan your Shiso planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Val Verde County, TX?

Val Verde County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is February 17 and first fall frost is December 7.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Val Verde County gardeners in Zone 8a organize planting dates, track what's growing, and never miss a planting window.

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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 Val Verde County, TX. Local conditions may vary. Last updated: April 2026.