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When to Plant Kai Lan in Sioux County, NE

Sioux County, Nebraska Zone 5a May

May in Sioux County, Nebraska — your action list

Welcome to May in Zone 5a. These are the moves that will have the biggest impact on your growing season.

Avg. last frost May 16
Avg. first frost September 22
Soil temp (4") 53°F
Watering High
Pest pressure Low
Daylight 14.4 hrs
  1. Get kai lan in the ground

    Plant tomatoes deep — bury the stem up to the first true leaves to grow extra roots. Everything else goes in at the same depth it grew in the tray.

  2. Put kai lan seeds straight in the ground

    Mark the row. Birds and stray feet both have opinions about unmarked beds.

June will be here before you know it — start on
  • Starting indoors: kai lan

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Kai lan (Chinese broccoli) is a brassica grown for its thick, glossy stems and small flower buds. It has a slightly bitter, broccoli-like flavor essential in Cantonese cooking.

Sioux County, Nebraska is in USDA Zone 5a. The average last spring frost is May 16 and the first fall frost is September 22, giving you a growing season of approximately 129 days.

At an elevation of 775 feet, Sioux County receives approximately 24.4 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Kai Lan to ensure they mature before fall.

Sioux County, NE (Zone 5a) Short season
129 days
Last Spring Frost May 16
129 growing days
First Fall Frost September 22

Sioux County Soil Profile

Soil Type

Loam

Soil pH

6.3-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (49 days to spare)
Start indoors: Apr 6 Transplant: May 11 🍅 Harvest: Jun 29 – Jul 27
Recommended (50%) ✓ Fits season (52 days to spare)
Start indoors: Apr 11 Transplant: May 16 🍅 Harvest: Jul 4 – Aug 1
Safe Start (90%) ✓ Fits season (44 days to spare)
Start indoors: May 5 Transplant: Jun 9 🍅 Harvest: Jul 28 – Aug 25

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 Sioux County

How your county's soil matches Kai Lan's growing requirements.

Soil pH

Your soil pH (6.3–7.2) is within Kai Lan's preferred range (6.0–7.5).

Soil Texture

The loam soil in Sioux County is excellent for Kai Lan — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.3%) — Kai Lan will thrive.

How to Plant Kai Lan

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 Kai Lan

3
successive plantings in your 129-day season

Sow every 5.1 weeks. Last sowing by Jul 24 to harvest before frost.

For a dedicated fall crop, sow by Jul 14.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 283 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Kai Lan

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

Month Kai Lan Needs Rainfall You Supplement Action
Jan 1.7" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 2.3" 0" ❄️ Dormant
Apr 2.5" 0" ❄️ Dormant
May 4.3" 2.7" 1.6" 💧 Light watering
Jun 4.3" 1.6" 2.7" 🚿 Regular watering
Jul 4.3" 2" 2.3" 🚿 Regular watering
Aug 4.3" 2.8" 1.5" 💧 Light watering
Sep 4.3" 2.2" 2.1" 💧 Light watering
Oct 2.1" 0" ❄️ Dormant
Nov 1.6" 0" ❄️ Dormant
Dec 1.5" 0" ❄️ Dormant

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

Kai Lan 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.

Kai Lan needs ~682 GDD — county provides 1,677 GDD Excellent fit

Kai Lan Planting Timeline — Sioux County, NE

Kai Lan Planting Calendar

Activity When Date Range
Start Indoors April 11 Apr 11 – Apr 25
Transplant Outdoors May 16 May 16 – May 30
Direct Sow May 2 May 2 – May 23
Harvest July 4 Jul 4 – Aug 1
Fall Sowing July 14 Jul 14 – Jul 28

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

45–60 days

🧪 Soil pH

Needs 6–7.5 · Your soil: ideal

🗺️ USDA Zone

Zone 5a

📆 Growing Season

129 days in Sioux County

Growing Tips for Kai Lan in Sioux County

Direct sow Kai Lan outdoors after May 16 in Sioux County when soil has warmed and frost danger has passed.

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

Sioux County receives only 24" of rain annually. Kai Lan needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Direct sow in spring or fall. Harvest when flower buds first appear but before they open. Cut stems at the base to encourage side shoots. Prefers cool weather.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Kai Lan in Sioux County, NE?

Sioux County is in Zone 5a with an average last frost of May 16. Plan your Kai Lan planting based on this frost date — see the calendar above for exact timing.

What planting zone is Sioux County, NE?

Sioux County, Nebraska is in USDA Hardiness Zone 5a. The average last spring frost is May 16 and first fall frost is September 22.

🌱

Your Sioux County Garden Planner — Free

A 24-page printable planner built for Sioux 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.

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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 Sioux County, NE. 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.