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When to Plant Tatsoi in San Diego County, CA

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.

San Diego County, California is in USDA Zone 10b. The average last spring frost is April 16 and the first fall frost is November 1, giving you a growing season of approximately 199 days.

At an elevation of 2,613 feet, San Diego County receives approximately 18.2 inches of rainfall annually with predominantly loam soil. Summer highs average 92ยฐF, providing good warmth for Tatsoi during the growing season. With low rainfall, drip irrigation is essential for growing Tatsoi successfully. Mulch heavily to conserve soil moisture.

San Diego County, CA (Zone 10b) Moderate season
199 days
Last Spring Frost April 16
199 growing days
First Fall Frost November 1

San Diego County Soil Profile

Soil Type

Loam

Soil pH

5.7-7.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (124 days to spare)
Start indoors: Mar 12 Transplant: Apr 9 🍅 Harvest: May 14 – Jun 18
Recommended (50%) ✓ Fits season (129 days to spare)
Start indoors: Mar 19 Transplant: Apr 16 🍅 Harvest: May 21 – Jun 25
Safe Start (90%) ✓ Fits season (125 days to spare)
Start indoors: Apr 23 Transplant: May 21 🍅 Harvest: Jun 25 – Jul 30

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
0.4″/week
You supply
0.7″/week
Watering frequency 2-3 times/week
Season total 1,309 gal / 100 sq ft
Drought risk

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

Tatsoi needs ~808 GDD — county provides 3,781 GDD Excellent fit

Tatsoi Planting Timeline โ€” San Diego County, CA

Tatsoi Planting Calendar

Activity When Date Range
Start Indoors March 19 Mar 19 โ€“ Apr 2
Transplant Outdoors April 16 Apr 16 โ€“ Apr 30
Direct Sow March 26 Mar 26 โ€“ Apr 16
Fall Sowing September 6 Sep 6 โ€“ Sep 20
Harvest May 21 May 21 โ€“ Jun 25

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 Start Indoors Transplant Outdoors Direct Sow
May Harvest
June Harvest
July โ€”
August โ€”
September Fall Sowing
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 10b

Growing Season

199 days

Growing Tips for San Diego 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 San Diego County, CA?

San Diego County is in Zone 10b with an average last frost of April 16. Plan your Tatsoi planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is San Diego County, CA?

San Diego County, California is in USDA Hardiness Zone 10b. The average last spring frost is April 16 and first fall frost is November 1.

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Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help San Diego County gardeners in Zone 10b 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 San Diego County, CA. Local conditions may vary. Last updated: April 2026.