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When to Plant Tatsoi in Warren County, IL

Tatsoi is a compact Asian green forming beautiful rosettes of dark, spoon-shaped leaves with a mild mustard flavor. It is extremely cold-hardy and versatile.

Warren County, Illinois is in USDA Zone 5a. The average last spring frost is April 13 and the first fall frost is October 21, giving you a growing season of approximately 191 days.

At an elevation of 801 feet, Warren County receives approximately 36.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87ยฐF, providing good warmth for Tatsoi during the growing season.

Warren County, IL (Zone 5a) Moderate season
191 days
Last Spring Frost April 13
191 growing days
First Fall Frost October 21

Warren County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (120 days to spare)
Start indoors: Mar 3 Transplant: Apr 7 🍅 Harvest: May 12 – Jun 16
Recommended (50%) ✓ Fits season (121 days to spare)
Start indoors: Mar 9 Transplant: Apr 13 🍅 Harvest: May 18 – Jun 22
Safe Start (90%) ✓ Fits season (125 days to spare)
Start indoors: Mar 24 Transplant: Apr 28 🍅 Harvest: Jun 2 – Jul 7

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
0.8″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 421 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Tatsoi needs ~648 GDD — county provides 2,912 GDD Excellent fit

Tatsoi Planting Timeline โ€” Warren County, IL

Tatsoi Planting Calendar

Activity When Date Range
Start Indoors March 9 Mar 9 โ€“ Mar 23
Transplant Outdoors April 13 Apr 13 โ€“ Apr 27
Direct Sow March 30 Mar 30 โ€“ Apr 20
Fall Sowing August 12 Aug 12 โ€“ Aug 26
Harvest May 18 May 18 โ€“ Jun 22

Plant 0.5" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

Sun

Partial Shade (3-6 hours)

Water

Moderate โ€” regular watering

Days to Maturity

35โ€“50 days

Soil pH

6 โ€“ 7.5

USDA Zone

Zone 5a

Growing Season

191 days

Growing Tips for Warren County

Direct sow in spring or fall. Tatsoi tolerates frost down to 15F. Harvest outer leaves or cut whole rosettes. Excellent in salads, stir-fries, or lightly wilted.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Level Up Your Garden

Frequently Asked Questions

When should I plant Tatsoi in Warren County, IL?

Warren County is in Zone 5a with an average last frost of April 13. Plan your Tatsoi planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Warren County, IL?

Warren County, Illinois is in USDA Hardiness Zone 5a. The average last spring frost is April 13 and first fall frost is October 21.

๐ŸŒฑ

Plan Your Garden with Confidence

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