Blog

When to Plant Shiso in Mora 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.

Mora County, New Mexico is in USDA Zone 5a. The average last spring frost is May 22 and the first fall frost is September 25, giving you a growing season of approximately 126 days.

At an elevation of 6,818 feet, Mora County receives approximately 16.9 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 87ยฐF, 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.

Mora County, NM (Zone 5a) Short season
126 days
Last Spring Frost May 22
126 growing days
First Fall Frost September 25

Mora County Soil Profile

Soil Type

Sandy Loam

Soil pH

6.8-8.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (1 days to spare)
Start indoors: Mar 23 Transplant: May 25 🍅 Harvest: Jul 20 – Sep 14
Recommended (50%) ✓ Fits season (0 days to spare)
Start indoors: Apr 3 Transplant: Jun 5 🍅 Harvest: Jul 31 – Sep 25
Safe Start (90%) ✗ May not fit
Start indoors: May 3 Transplant: Jul 5 🍅 Harvest: Aug 30 – Oct 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 Mora County

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

Soil pH

Your soil pH (6.8โ€“8.4) is more alkaline than Shiso prefers (5.5โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Mora 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

2
successive plantings in your 126-day season

Sow every 5.7 weeks. Last sowing by Jul 17 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.6″/week
You supply
0.9″/week
Watering frequency 2-3 times/week
Season total 991 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" 0" โ„๏ธ Dormant
Feb โ€” 0.9" 0" โ„๏ธ Dormant
Mar โ€” 0.9" 0" โ„๏ธ Dormant
Apr โ€” 0.6" 0" โ„๏ธ Dormant
May 4.3" 0.4" 3.9" ๐Ÿšฟ Regular watering
Jun 4.3" 0.6" 3.7" ๐Ÿšฟ Regular watering
Jul 4.3" 3" 1.3" ๐Ÿ’ง Light watering
Aug 4.3" 3.7" 0.6" ๐Ÿ’ง Light watering
Sep 4.3" 2" 2.3" ๐Ÿšฟ Regular watering
Oct โ€” 1.5" 0" โ„๏ธ Dormant
Nov โ€” 1" 0" โ„๏ธ Dormant
Dec โ€” 1.2" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Sep in Mora 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 ~915 GDD — county provides 1,921 GDD Excellent fit

Shiso Planting Timeline โ€” Mora County, NM

Shiso Planting Calendar

Activity When Date Range
Start Indoors April 3 Apr 3 โ€“ Apr 17
Transplant Outdoors June 5 Jun 5 โ€“ Jun 19
Direct Sow May 29 May 29 โ€“ Jun 19
Harvest July 31 Jul 31 โ€“ Sep 25

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Start Indoors
May Direct Sow
June Transplant Outdoors Direct Sow
July Harvest
August Harvest
September Harvest
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 5a

๐Ÿ“† Growing Season

126 days in Mora County

Growing Tips for Shiso in Mora County

Direct sow Shiso outdoors after May 22 in Mora County when soil has warmed and frost danger has passed.

Sandy soil in Mora 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.

Mora 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 Mora County, NM?

Mora County is in Zone 5a with an average last frost of May 22. Plan your Shiso planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Mora County, NM?

Mora County, New Mexico is in USDA Hardiness Zone 5a. The average last spring frost is May 22 and first fall frost is September 25.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Mora County gardeners in Zone 5a 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 Mora County, NM. Local conditions may vary. Last updated: April 2026.