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When to Plant Shiso in Putnam County, NY

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.

Putnam County, New York is in USDA Zone 6a. The average last spring frost is April 10 and the first fall frost is November 1, giving you a growing season of approximately 205 days.

At an elevation of 722 feet, Putnam County receives approximately 40.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89ยฐF, providing good warmth for Shiso during the growing season.

Putnam County, NY (Zone 6a) Long season
205 days
Last Spring Frost April 10
205 growing days
First Fall Frost November 1

Putnam County Soil Profile

Soil Type

Silt Loam

Soil pH

5.1-6.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (76 days to spare)
Start indoors: Feb 12 Transplant: Apr 16 🍅 Harvest: Jun 11 – Aug 6
Recommended (50%) ✓ Fits season (79 days to spare)
Start indoors: Feb 20 Transplant: Apr 24 🍅 Harvest: Jun 19 – Aug 14
Safe Start (90%) ✓ Fits season (75 days to spare)
Start indoors: Mar 22 Transplant: May 24 🍅 Harvest: Jul 19 – Sep 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 Putnam County

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

Soil pH

Your soil pH (5.1โ€“6.3) overlaps with Shiso's range (5.5โ€“7.0), though not a perfect match.

Soil Texture

The silt loam soil in Putnam County is excellent for Shiso โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.6%). Annual compost additions will help Shiso.

How to Plant Shiso

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

Succession Planting Shiso

4
successive plantings in your 205-day season

Sow every 5.7 weeks. Last sowing by Aug 23 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 314 gal / 100 sq ft

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€” 3.1" 0" โ„๏ธ Dormant
Feb โ€” 2.6" 0" โ„๏ธ Dormant
Mar โ€” 3.6" 0" โ„๏ธ Dormant
Apr 4.3" 3.2" 1.1" ๐Ÿ’ง Light watering
May 4.3" 3.9" 0.4" ๐Ÿ’ง Light watering
Jun 4.3" 3.7" 0.6" ๐Ÿ’ง Light watering
Jul 4.3" 4" 0.3" ๐Ÿ’ง Light watering
Aug 4.3" 3.2" 1.1" ๐Ÿ’ง Light watering
Sep 4.3" 3.3" 1" ๐Ÿ’ง Light watering
Oct 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
Nov 4.3" 3.4" 0.9" ๐Ÿ’ง Light watering
Dec โ€” 2.8" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Nov in Putnam 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 ~1,005 GDD — county provides 3,433 GDD Excellent fit

Shiso Planting Timeline โ€” Putnam County, NY

Shiso Planting Calendar

Activity When Date Range
Start Indoors February 20 Feb 20 โ€“ Mar 6
Transplant Outdoors April 24 Apr 24 โ€“ May 8
Direct Sow April 17 Apr 17 โ€“ May 8
Harvest June 19 Jun 19 โ€“ Aug 14

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

Month-by-Month Timeline

MonthActivities
January โ€”
February Start Indoors
March Start Indoors
April Transplant Outdoors Direct Sow
May Transplant Outdoors Direct Sow
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 Only during dry spells

๐Ÿ“… Days to Maturity

50โ€“70 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 6a

๐Ÿ“† Growing Season

205 days in Putnam County

Growing Tips for Shiso in Putnam County

Direct sow Shiso outdoors after April 10 in Putnam County when soil has warmed and frost danger has passed.

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 Putnam County, NY?

Putnam County is in Zone 6a with an average last frost of April 10. Plan your Shiso planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Putnam County, NY?

Putnam County, New York is in USDA Hardiness Zone 6a. The average last spring frost is April 10 and first fall frost is November 1.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Putnam County gardeners in Zone 6a 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 Putnam County, NY. Local conditions may vary. Last updated: April 2026.