Blog

When to Plant Shiso in Ulster County, NY

Ulster County, New York Zone 6a May

Ulster County, New York gardeners: here's your May plan

May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Ulster County, New York.

Avg. last frost April 24
Avg. first frost October 23
Soil temp (4") 64°F
Watering Low
Pest pressure Low
Daylight 14.4 hrs
  1. Harden off and plant shiso

    Harden off for 7 days — a little more sun each day — before planting. That's the difference between a seedling that thrives and one that stalls.

  2. Direct-sow shiso

    Keep the top inch of soil moist until germination — a gentle morning watering for 5–7 days does the job.

A few tasks this May that'll pay off in June
  • Starting indoors: shiso

Instant PDF download. No spam, unsubscribe any time.

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.

Ulster County, New York is in USDA Zone 6a. The average last spring frost is April 24 and the first fall frost is October 23, giving you a growing season of approximately 182 days.

At an elevation of 1,121 feet, Ulster County receives approximately 39.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Shiso during the growing season.

Ulster County, NY (Zone 6a) Moderate season
182 days
Last Spring Frost April 24
182 growing days
First Fall Frost October 23
Share this guide:

Ulster County Soil Profile

Soil Type

Silt Loam

Soil pH

4.8-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (57 days to spare)
Start indoors: Feb 26 Transplant: Apr 30 🍅 Harvest: Jun 25 – Aug 20
Recommended (50%) ✓ Fits season (56 days to spare)
Start indoors: Mar 6 Transplant: May 8 🍅 Harvest: Jul 3 – Aug 28
Safe Start (90%) ✓ Fits season (51 days to spare)
Start indoors: Mar 26 Transplant: May 28 🍅 Harvest: Jul 23 – Sep 17

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 Ulster County

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

Soil pH

Your soil pH (4.8–6.8) overlaps with Shiso's range (5.5–7.0), though not a perfect match.

Soil Texture

The silt loam soil in Ulster County is excellent for Shiso — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.7%). 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 182-day season

Sow every 5.7 weeks. Last sowing by Aug 14 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 151 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 2.4" 0" ❄️ Dormant
Feb 2.4" 0" ❄️ Dormant
Mar 3.2" 0" ❄️ Dormant
Apr 4.3" 2.9" 1.4" 💧 Light watering
May 4.3" 4" 0.3" 💧 Light watering
Jun 4.3" 3.7" 0.6" 💧 Light watering
Jul 4.3" 4.4" 0" ✅ Rainfall sufficient
Aug 4.3" 3.9" 0.4" 💧 Light watering
Sep 4.3" 3.5" 0.8" 💧 Light watering
Oct 4.3" 3.5" 0.8" 💧 Light watering
Nov 2.7" 0" ❄️ Dormant
Dec 2.6" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Ulster County). Supplement amounts are based on average rainfall — 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" — 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.

Shiso needs ~1,005 GDD — county provides 3,048 GDD Excellent fit

Shiso Planting Timeline — Ulster County, NY

Shiso Planting Calendar

Activity When Date Range
Start Indoors March 6 Mar 6 – Mar 20
Transplant Outdoors May 8 May 8 – May 22
Direct Sow May 1 May 1 – May 22
Harvest July 3 Jul 3 – Aug 28

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April
May Transplant Outdoors Direct Sow
June
July Harvest
August Harvest
September
October
November
December
Share this guide:

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 5.5–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6a

📆 Growing Season

182 days in Ulster County

Growing Tips for Shiso in Ulster County

Direct sow Shiso outdoors after April 24 in Ulster 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 Ulster County, NY?

Ulster County is in Zone 6a with an average last frost of April 24. Plan your Shiso planting based on this frost date — see the calendar above for exact timing.

What planting zone is Ulster County, NY?

Ulster County, New York is in USDA Hardiness Zone 6a. The average last spring frost is April 24 and first fall frost is October 23.

🌱

Your Ulster County Garden Planner — Free

A 24-page printable planner built for Ulster County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

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

Sources & credits

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