Blog

When to Plant Tatsoi in Woodbury County, IA

Woodbury County, Iowa Zone 5a May

Your May planting checklist for Woodbury County, Iowa

Here's what deserves your attention in Woodbury County, Iowa this month. Everything below is tailored to Zone 5a and timed around your local frost dates.

Avg. last frost April 26
Avg. first frost October 6
Soil temp (4") 52°F
Watering Low
Pest pressure Low
Daylight 14.4 hrs
  1. Time to start tatsoi inside

    A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.

  2. Basket week: tatsoi

    If you can't use it all right away, check the food-preservation section of your planner.

Coming up in June — start thinking about
  • First harvests: tatsoi

Instant PDF download. No spam, unsubscribe any time.

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.

Woodbury County, Iowa is in USDA Zone 5a. The average last spring frost is April 26 and the first fall frost is October 6, giving you a growing season of approximately 163 days.

At an elevation of 1,388 feet, Woodbury County receives approximately 40.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Tatsoi to ensure they mature before fall.

Woodbury County, IA (Zone 5a) Moderate season
163 days
Last Spring Frost April 26
163 growing days
First Fall Frost October 6

Woodbury County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (99 days to spare)
Start indoors: Mar 13 Transplant: Apr 17 🍅 Harvest: May 22 – Jun 26
Recommended (50%) ✓ Fits season (93 days to spare)
Start indoors: Mar 22 Transplant: Apr 26 🍅 Harvest: May 31 – Jul 5
Safe Start (90%) ✓ Fits season (97 days to spare)
Start indoors: Apr 6 Transplant: May 11 🍅 Harvest: Jun 15 – Jul 20

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 Woodbury County

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

Soil pH

Your soil pH (5.8–6.8) overlaps with Tatsoi's range (6.0–7.5), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Tatsoi.

Organic Matter

Organic matter is excellent (4.1%) — Tatsoi will thrive.

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

5
successive plantings in your 163-day season

Sow every 4 weeks. Last sowing by Aug 17 to harvest before frost.

For a dedicated fall crop, sow by Jul 28.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 383 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 1.5" 0" ❄️ Dormant
Feb 1.9" 0" ❄️ Dormant
Mar 2.8" 0" ❄️ Dormant
Apr 4.3" 3.5" 0.8" 💧 Light watering
May 4.3" 4.4" 0" ✅ Rainfall sufficient
Jun 4.3" 5.5" 0" ✅ Rainfall sufficient
Jul 4.3" 4.5" 0" ✅ Rainfall sufficient
Aug 4.3" 4.9" 0" ✅ Rainfall sufficient
Sep 4.3" 3.3" 1" 💧 Light watering
Oct 4.3" 3.4" 0.9" 💧 Light watering
Nov 2.5" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Woodbury 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 ~425 GDD — county provides 1,630 GDD Excellent fit

Tatsoi Planting Timeline — Woodbury County, IA

Tatsoi Planting Calendar

Activity When Date Range
Start Indoors March 22 Mar 22 – Apr 5
Transplant Outdoors April 26 Apr 26 – May 10
Direct Sow April 12 Apr 12 – May 3
Harvest May 31 May 31 – Jul 5
Fall Sowing July 28 Jul 28 – Aug 11

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

Month-by-Month Timeline

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

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 5a

📆 Growing Season

163 days in Woodbury County

Growing Tips for Tatsoi in Woodbury County

Direct sow Tatsoi outdoors after April 26 in Woodbury County when soil has warmed and frost danger has passed.

Your generous 163.0-day season in Woodbury 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 Woodbury County, IA?

Woodbury County is in Zone 5a with an average last frost of April 26. Plan your Tatsoi planting based on this frost date — see the calendar above for exact timing.

What planting zone is Woodbury County, IA?

Woodbury County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 26 and first fall frost is October 6.

🌱

Your Woodbury County Garden Planner — Free

A 24-page printable planner built for Woodbury County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Woodbury County, IA. 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.