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When to Plant Shiso in Lea County, NM

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.

Lea County, New Mexico is in USDA Zone 7b. The average last spring frost is April 2 and the first fall frost is November 7, giving you a growing season of approximately 219 days.

At an elevation of 4,857 feet, Lea County receives approximately 17.1 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 93ยฐF, providing good warmth for Shiso during the growing season. 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. With low rainfall, drip irrigation is essential for growing Shiso successfully. Mulch heavily to conserve soil moisture.

Lea County, NM (Zone 7b) Long season
219 days
Last Spring Frost April 2
219 growing days
First Fall Frost November 7

Lea County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.3-8.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (91 days to spare)
Start indoors: Feb 3 Transplant: Apr 7 🍅 Harvest: Jun 2 – Jul 28
Recommended (50%) ✓ Fits season (93 days to spare)
Start indoors: Feb 12 Transplant: Apr 16 🍅 Harvest: Jun 11 – Aug 6
Safe Start (90%) ✓ Fits season (86 days to spare)
Start indoors: Mar 3 Transplant: May 5 🍅 Harvest: Jun 30 – Aug 25

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 Lea County

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

Soil pH

Your soil pH (7.3โ€“8.9) is more alkaline than Shiso prefers (5.5โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Drainage

Drainage is adequate for Shiso.

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

5
successive plantings in your 219-day season

Sow every 5.7 weeks. Last sowing by Aug 29 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.3″/week
You supply
1.2″/week
Watering frequency 2-3 times/week
Season total 2,274 gal / 100 sq ft
Drought risk

Water stress score is 10/10 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€” 1.3" 0" โ„๏ธ Dormant
Feb โ€” 0.9" 0" โ„๏ธ Dormant
Mar โ€” 0.8" 0" โ„๏ธ Dormant
Apr 4.3" 0.6" 3.7" ๐Ÿšฟ Regular watering
May 4.3" 0.3" 4" ๐Ÿšฟ Regular watering
Jun 4.3" 0.5" 3.8" ๐Ÿšฟ Regular watering
Jul 4.3" 2.9" 1.4" ๐Ÿ’ง Light watering
Aug 4.3" 3.7" 0.6" ๐Ÿ’ง Light watering
Sep 4.3" 2.4" 1.9" ๐Ÿ’ง Light watering
Oct 4.3" 1.6" 2.7" ๐Ÿšฟ Regular watering
Nov 4.3" 1.1" 3.2" ๐Ÿšฟ Regular watering
Dec โ€” 1" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Nov in Lea 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 ~1,185 GDD — county provides 4,325 GDD Excellent fit

Shiso Planting Timeline โ€” Lea County, NM

Shiso Planting Calendar

Activity When Date Range
Start Indoors February 12 Feb 12 โ€“ Feb 26
Transplant Outdoors April 16 Apr 16 โ€“ Apr 30
Direct Sow April 9 Apr 9 โ€“ Apr 30
Harvest June 11 Jun 11 โ€“ Aug 6

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท 2-3 times/week

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 7b

๐Ÿ“† Growing Season

219 days in Lea County

Growing Tips for Shiso in Lea County

Direct sow Shiso outdoors after April 02 in Lea County when soil has warmed and frost danger has passed.

Sandy soil in Lea 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.

Lea County receives only 17" of rain annually. Shiso needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

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 Lea County, NM?

Lea County is in Zone 7b with an average last frost of April 2. Plan your Shiso planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Lea County, NM?

Lea County, New Mexico is in USDA Hardiness Zone 7b. The average last spring frost is April 2 and first fall frost is November 7.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Lea County gardeners in Zone 7b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

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