When to Plant Tatsoi in Williamson 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.
Williamson County, Illinois is in USDA Zone 6b. The average last spring frost is April 10 and the first fall frost is October 20, giving you a growing season of approximately 193 days.
At an elevation of 1,253 feet, Williamson County receives approximately 38.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Tatsoi during the growing season.
Williamson County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-7.2
Drainage
Well Drained
Plant Planting Risk Windows
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
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Tatsoi Planting Timeline — Williamson County, IL
Tatsoi Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 6 | Mar 6 – Mar 20 |
| Transplant Outdoors | April 10 | Apr 10 – Apr 24 |
| Direct Sow | March 27 | Mar 27 – Apr 17 |
| Fall Sowing | August 11 | Aug 11 – Aug 25 |
| Harvest | May 15 | May 15 – Jun 19 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | — |
| August | Fall Sowing |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Partial Shade (3-6 hours)
Water
Moderate — regular watering
Days to Maturity
35–50 days
Soil pH
6 – 7.5
USDA Zone
Zone 6b
Growing Season
193 days
Growing Tips for Williamson 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
Level Up Your Garden
Tatsoi in Other Locations
Frequently Asked Questions
When should I plant Tatsoi in Williamson County, IL?
Williamson County is in Zone 6b with an average last frost of April 10. Plan your Tatsoi planting based on this frost date — see the calendar above for exact timing.
What planting zone is Williamson County, IL?
Williamson County, Illinois is in USDA Hardiness Zone 6b. The average last spring frost is April 10 and first fall frost is October 20.
Plan Your Garden with Confidence
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