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When to Plant Tatsoi in Yolo County, CA

Yolo County, California Zone 9a April

April in Yolo County, California — your action list

We've pulled the most time-sensitive tasks for Yolo County, California this April and put them front and centre. Tackle them in order.

Avg. last frost February 9
Avg. first frost December 3
Soil temp (4") 67°F
Watering High
Pest pressure High
Daylight 13 hrs
  1. Bring in the tatsoi

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

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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.

Yolo County, California is in USDA Zone 9a. The average last spring frost is February 9 and the first fall frost is December 3, giving you a growing season of approximately 297 days.

At an elevation of 163 feet, Yolo County receives approximately 27.7 inches of rainfall annually with predominantly loam soil. Summer highs average 95°F, so Tatsoi may need afternoon shade and extra watering during peak heat.

Yolo County, CA (Zone 9a) Year-round
297 days
Last Spring Frost February 9
297 growing days
First Fall Frost December 3
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Yolo County Soil Profile

Soil Type

Loam

Soil pH

6.7-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (235 days to spare)
Start indoors: Dec 28 Transplant: Jan 25 🍅 Harvest: Mar 1 – Apr 5
Recommended (50%) ✓ Fits season (227 days to spare)
Start indoors: Jan 12 Transplant: Feb 9 🍅 Harvest: Mar 16 – Apr 20
Safe Start (90%) ✓ Fits season (211 days to spare)
Start indoors: Feb 13 Transplant: Mar 13 🍅 Harvest: Apr 17 – May 22

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 Yolo County

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

Soil pH

Your soil pH (6.7–7.8) overlaps with Tatsoi's range (6.0–7.5), though not a perfect match.

Soil Texture

The loam soil in Yolo County is excellent for Tatsoi — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.4%). Annual compost additions will help Tatsoi.

How to Plant Tatsoi

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Tatsoi

10
successive plantings in your 297-day season

Sow every 4 weeks. Last sowing by Oct 14 to harvest before frost.

For a dedicated fall crop, sow by Oct 08.

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 1,940 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Tatsoi

Tatsoi needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Tatsoi Needs Rainfall You Supplement Action
Jan 6" 0" ❄️ Dormant
Feb 4.3" 5.4" 0" ✅ Rainfall sufficient
Mar 4.3" 4" 0.3" 💧 Light watering
Apr 4.3" 2.3" 2" 💧 Light watering
May 4.3" 0.8" 3.5" 🚿 Regular watering
Jun 4.3" 0.1" 4.2" 🚿 Regular watering
Jul 4.3" 0" 4.3" 🚿 Regular watering
Aug 4.3" 0" 4.3" 🚿 Regular watering
Sep 4.3" 0.3" 4" 🚿 Regular watering
Oct 4.3" 1.1" 3.2" 🚿 Regular watering
Nov 4.3" 2.6" 1.7" 💧 Light watering
Dec 4.3" 5.1" 0" ✅ Rainfall sufficient

Water needs are for active growing months only (Feb–Dec in Yolo County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Tatsoi 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.

Tatsoi needs ~903 GDD — county provides 6,332 GDD Excellent fit

Tatsoi Planting Timeline — Yolo County, CA

Tatsoi Planting Calendar

Activity When Date Range
Start Indoors January 12 Jan 12 – Jan 26
Transplant Outdoors February 9 Feb 9 – Feb 23
Direct Sow January 19 Jan 19 – Feb 9
Harvest March 16 Mar 16 – Apr 20
Fall Sowing October 8 Oct 8 – Oct 22

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

Month-by-Month Timeline

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

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · 2-3 times/week

📅 Days to Maturity

35–50 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 9a

📆 Growing Season

297 days in Yolo County

Growing Tips for Tatsoi in Yolo County

Direct sow Tatsoi outdoors after February 09 in Yolo County when soil has warmed and frost danger has passed.

Your generous 298.0-day season in Yolo County allows multiple plantings of Tatsoi. Sow every 17.0 days for continuous harvest.

Common pests for Tatsoi in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Tatsoi in Yolo County, CA?

Yolo County is in Zone 9a with an average last frost of February 9. Plan your Tatsoi planting based on this frost date — see the calendar above for exact timing.

What planting zone is Yolo County, CA?

Yolo County, California is in USDA Hardiness Zone 9a. The average last spring frost is February 9 and first fall frost is December 3.

🌱

Your Yolo County Garden Planner — Free

A 24-page printable planner built for Yolo County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Yolo County, CA. Local conditions may vary. Last updated: April 2026.

Sources & credits

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