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When to Plant Tatsoi in Jefferson County, TN

Jefferson County, Tennessee Zone 7b May

May to-do list for Jefferson County, Tennessee

A quick May briefing for Jefferson County, Tennessee gardeners — what's urgent, what's next, and what can wait.

Avg. last frost April 15
Avg. first frost October 22
Soil temp (4") 59°F
Watering Moderate
Pest pressure Moderate
Daylight 13.9 hrs
  1. Get tatsoi seeds going inside

    You're about 24 weeks out from your last frost — the perfect window to get these germinating indoors.

  2. Pick tatsoi

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

To set up a strong June, finish these tasks
  • First harvests: tatsoi

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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.

Jefferson County, Tennessee is in USDA Zone 7b. The average last spring frost is April 15 and the first fall frost is October 22, giving you a growing season of approximately 190 days.

At an elevation of 3,886 feet, Jefferson County receives approximately 44.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 93°F, providing good warmth for Tatsoi during the growing season.

Jefferson County, TN (Zone 7b) Moderate season
190 days
Last Spring Frost April 15
190 growing days
First Fall Frost October 22
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Jefferson County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (123 days to spare)
Start indoors: Mar 4 Transplant: Apr 8 🍅 Harvest: May 13 – Jun 17
Recommended (50%) ✓ Fits season (120 days to spare)
Start indoors: Mar 11 Transplant: Apr 15 🍅 Harvest: May 20 – Jun 24
Safe Start (90%) ✓ Fits season (115 days to spare)
Start indoors: Mar 28 Transplant: May 2 🍅 Harvest: Jun 6 – Jul 11

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 Jefferson County

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

Soil pH

Your soil pH (5.4–6.8) overlaps with Tatsoi's range (6.0–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.2%). Annual compost additions will help Tatsoi.

How to Plant Tatsoi

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

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Tatsoi

6
successive plantings in your 190-day season

Sow every 4 weeks. Last sowing by Sep 02 to harvest before frost.

For a dedicated fall crop, sow by Aug 13.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
You supply
0.0″/week
Watering frequency Only during dry spells
Season total 16 gal / 100 sq ft

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 3.4" 0" ❄️ Dormant
Feb 3.8" 0" ❄️ Dormant
Mar 4" 0" ❄️ Dormant
Apr 4.3" 3.4" 0.9" 💧 Light watering
May 4.3" 3.6" 0.7" 💧 Light watering
Jun 4.3" 4.1" 0.2" 💧 Light watering
Jul 4.3" 4.5" 0" ✅ Rainfall sufficient
Aug 4.3" 3.9" 0.4" 💧 Light watering
Sep 4.3" 3.7" 0.6" 💧 Light watering
Oct 4.3" 2.8" 1.5" 💧 Light watering
Nov 3.6" 0" ❄️ Dormant
Dec 3.9" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Jefferson 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 ~839 GDD — county provides 3,752 GDD Excellent fit

Tatsoi Planting Timeline — Jefferson County, TN

Tatsoi Planting Calendar

Activity When Date Range
Start Indoors March 11 Mar 11 – Mar 25
Transplant Outdoors April 15 Apr 15 – Apr 29
Direct Sow April 1 Apr 1 – Apr 22
Harvest May 20 May 20 – Jun 24
Fall Sowing August 13 Aug 13 – Aug 27

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

Month-by-Month Timeline

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

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

35–50 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 7b

📆 Growing Season

190 days in Jefferson County

Growing Tips for Tatsoi in Jefferson County

Direct sow Tatsoi outdoors after April 15 in Jefferson County when soil has warmed and frost danger has passed.

Your generous 190.0-day season in Jefferson 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 Jefferson County, TN?

Jefferson County is in Zone 7b with an average last frost of April 15. Plan your Tatsoi planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jefferson County, TN?

Jefferson County, Tennessee is in USDA Hardiness Zone 7b. The average last spring frost is April 15 and first fall frost is October 22.

🌱

Your Jefferson County Garden Planner — Free

A 24-page printable planner built for Jefferson County (Zone 7b). 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 Jefferson County, TN. Local conditions may vary. Last updated: May 2026.

Sources & credits

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