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When to Plant Shiso in Sevier County, UT

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.

Sevier County, Utah is in USDA Zone 5b. The average last spring frost is May 19 and the first fall frost is September 30, giving you a growing season of approximately 134 days.

At an elevation of 8,049 feet, Sevier County receives approximately 20.6 inches of rainfall annually with predominantly loam soil. Summer highs average 88ยฐF, providing good warmth for Shiso during the growing season.

Sevier County, UT (Zone 5b) Short season
134 days
Last Spring Frost May 19
134 growing days
First Fall Frost September 30

Sevier County Soil Profile

Soil Type

Loam

Soil pH

6.4-8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (10 days to spare)
Start indoors: Mar 20 Transplant: May 22 🍅 Harvest: Jul 17 – Sep 11
Recommended (50%) ✓ Fits season (8 days to spare)
Start indoors: Mar 31 Transplant: Jun 2 🍅 Harvest: Jul 28 – Sep 22
Safe Start (90%) ✓ Fits season (7 days to spare)
Start indoors: Apr 23 Transplant: Jun 25 🍅 Harvest: Aug 20 – Oct 15

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.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 507 gal / 100 sq ft
Drought risk

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

Shiso needs ~960 GDD — county provides 2,144 GDD Excellent fit

Shiso Planting Timeline โ€” Sevier County, UT

Shiso Planting Calendar

Activity When Date Range
Start Indoors March 31 Mar 31 โ€“ Apr 14
Transplant Outdoors June 2 Jun 2 โ€“ Jun 16
Direct Sow May 26 May 26 โ€“ Jun 16
Harvest July 28 Jul 28 โ€“ Sep 22

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors
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

Sun

Partial Shade (3-6 hours)

Water

Moderate โ€” regular watering

Days to Maturity

50โ€“70 days

Soil pH

5.5 โ€“ 7

USDA Zone

Zone 5b

Growing Season

134 days

Growing Tips for Sevier County

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

Level Up Your Garden

Frequently Asked Questions

When should I plant Shiso in Sevier County, UT?

Sevier County is in Zone 5b with an average last frost of May 19. Plan your Shiso planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Sevier County, UT?

Sevier County, Utah is in USDA Hardiness Zone 5b. The average last spring frost is May 19 and first fall frost is September 30.

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Plan Your Garden with Confidence

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