When to Plant Tatsoi in San Luis Obispo County, CA
Your April gardening checklist
April is a pivotal month for San Luis Obispo County, California gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Begin indoor sowing: tatsoi
Label every cell. You will absolutely forget which is which otherwise.
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Start harvesting tatsoi
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
May will be here before you know it — start on
- First harvests: tatsoi
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 Luis Obispo County, California is in USDA Zone 9b. The average last spring frost is March 23 and the first fall frost is November 9, giving you a growing season of approximately 231 days.
At an elevation of 2,412 feet, San Luis Obispo County receives approximately 18.4 inches of rainfall annually with predominantly loam soil. Summer highs average 98°F, so Tatsoi may need afternoon shade and extra watering during peak heat. With low rainfall, drip irrigation is essential for growing Tatsoi successfully. Mulch heavily to conserve soil moisture.
San Luis Obispo County Soil Profile
Soil Type
Loam
Soil pH
6.6-7.8
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.
Soil Compatibility in San Luis Obispo County
How your county's soil matches Tatsoi's growing requirements.
Soil pH
Your soil pH (6.6–7.8) overlaps with Tatsoi's range (6.0–7.5), though not a perfect match.
Soil Texture
The loam soil in San Luis Obispo County is excellent for Tatsoi — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.9%). Annual compost additions will help Tatsoi.
How to Plant Tatsoi
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Tatsoi
Sow every 4 weeks. Last sowing by Sep 20 to harvest before frost.
For a dedicated fall crop, sow by Sep 14.
Plant Water Budget
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 | — | 4" | 0" | ❄️ Dormant |
| Feb | — | 3.9" | 0" | ❄️ Dormant |
| Mar | 4.3" | 2.8" | 1.5" | 💧 Light watering |
| Apr | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
| May | 4.3" | 0.5" | 3.8" | 🚿 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" | 0.2" | 4.1" | 🚿 Regular watering |
| Oct | 4.3" | 0.8" | 3.5" | 🚿 Regular watering |
| Nov | 4.3" | 1.8" | 2.5" | 🚿 Regular watering |
| Dec | — | 2.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in San Luis Obispo 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 Planting Timeline — San Luis Obispo County, CA
Tatsoi Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 23 | Feb 23 – Mar 9 |
| Transplant Outdoors | March 23 | Mar 23 – Apr 6 |
| Direct Sow | March 2 | Mar 2 – Mar 23 |
| Harvest | April 27 | Apr 27 – Jun 1 |
| Fall Sowing | September 14 | Sep 14 – Sep 28 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Transplant Outdoors Direct Sow |
| April | Transplant Outdoors Harvest |
| May | Harvest |
| June | Harvest |
| July | — |
| August | — |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
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 9b
📆 Growing Season
231 days in San Luis Obispo County
Growing Tips for Tatsoi in San Luis Obispo County
Direct sow Tatsoi outdoors after March 23 in San Luis Obispo County when soil has warmed and frost danger has passed.
With summer highs reaching 98°F in San Luis Obispo County, provide afternoon shade for Tatsoi and water deeply in the morning.
Your generous 231.0-day season in San Luis Obispo 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.
San Luis Obispo County receives only 18" of rain annually. Tatsoi needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
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
Check more plant combinations with our Companion Planting Checker →
Tatsoi in Other Locations
Frequently Asked Questions
When should I plant Tatsoi in San Luis Obispo County, CA?
San Luis Obispo County is in Zone 9b with an average last frost of March 23. Plan your Tatsoi planting based on this frost date — see the calendar above for exact timing.
What planting zone is San Luis Obispo County, CA?
San Luis Obispo County, California is in USDA Hardiness Zone 9b. The average last spring frost is March 23 and first fall frost is November 9.
Your San Luis Obispo County Garden Planner — Free
A 24-page printable planner built for San Luis Obispo County (Zone 9b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.