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When to Plant Kale in Hubbard County, MN

Hubbard County, Minnesota Zone 3b May

Hubbard County, Minnesota gardeners: here's your May plan

May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Hubbard County, Minnesota.

Avg. last frost May 12
Avg. first frost September 27
Soil temp (4") 51°F
Watering Low
Pest pressure Low
Daylight 14.9 hrs
  1. Move kale into the garden

    Your last frost (May 12) has passed. These warm-season crops can handle outdoor soil now.

  2. Plant kale from seed, right in the garden

    Thin ruthlessly once seedlings are up. Crowded roots mean smaller crops from every plant.

To set up a strong June, finish these tasks
  • Starting indoors: kale

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Kale is an exceptionally hardy, nutrient-dense green available in curly, lacinato, and Russian varieties. It tolerates heavy frost and often tastes sweeter after cold exposure.

Hubbard County, Minnesota is in USDA Zone 3b. The average last spring frost is May 12 and the first fall frost is September 27, giving you a growing season of approximately 138 days.

At an elevation of 733 feet, Hubbard County receives approximately 32.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 79°F, so choose short-season varieties of Kale to ensure they mature before fall.

Hubbard County, MN (Zone 3b) Short season
138 days
Last Spring Frost May 12
138 growing days
First Fall Frost September 27

Hubbard County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (23 days to spare)
Start indoors: Mar 26 Transplant: May 7 🍅 Harvest: Jul 2 – Aug 27
Recommended (50%) ✓ Fits season (26 days to spare)
Start indoors: Mar 31 Transplant: May 12 🍅 Harvest: Jul 7 – Sep 1
Safe Start (90%) ✓ Fits season (28 days to spare)
Start indoors: Apr 10 Transplant: May 22 🍅 Harvest: Jul 17 – Sep 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 Hubbard County

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

Soil pH

Your soil pH (5.7–6.8) overlaps with Kale's range (6.0–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (5.2%) — Kale will thrive.

How to Plant Kale

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Succession Planting Kale

3
successive plantings in your 138-day season

Sow every 5.7 weeks. Last sowing by Jul 19 to harvest before frost.

For a dedicated fall crop, sow by Jul 05.

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Kale

Kale needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.

Month Kale Needs Rainfall You Supplement Action
Jan 1.1" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 2.3" 0" ❄️ Dormant
Apr 3" 0" ❄️ Dormant
May 3.5" 3.8" 0" ✅ Rainfall sufficient
Jun 3.5" 4.2" 0" ✅ Rainfall sufficient
Jul 3.5" 3.9" 0" ✅ Rainfall sufficient
Aug 3.5" 3.6" 0" ✅ Rainfall sufficient
Sep 3.5" 3.2" 0.3" 💧 Light watering
Oct 2.2" 0" ❄️ Dormant
Nov 2.3" 0" ❄️ Dormant
Dec 1.7" 0" ❄️ Dormant

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

Kale 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.

Kale needs ~555 GDD — county provides 1,276 GDD Excellent fit

Kale Planting Timeline — Hubbard County, MN

Kale Planting Calendar

Activity When Date Range
Start Indoors March 31 Mar 31 – Apr 14
Transplant Outdoors May 12 May 12 – May 26
Direct Sow May 5 May 5 – May 26
Harvest July 7 Jul 7 – Sep 1
Fall Sowing July 5 Jul 5 – Jul 19

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.8"/week · Natural rainfall sufficient

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 3b

📆 Growing Season

138 days in Hubbard County

Growing Tips for Kale in Hubbard County

Direct sow Kale outdoors after May 12 in Hubbard County when soil has warmed and frost danger has passed.

Common pests for Kale 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 or transplant in early spring or late summer. Harvest outer leaves first to keep plants productive. Kale overwinters in many climates and can provide greens all year.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries
  • Tomatoes

Check more plant combinations with our Companion Planting Checker →

🌾 Save Your Own Kale Seeds
Life Cycle Biennial
Pollination Cross-Pollinated (insects)
How to Collect Allow 2nd year flower stalks to dry. Harvest pods when tan.
Storage Store airtight; viable 5 years at 35°F, under 50% humidity.

Isolate 1/2 mile from other brassicas (broccoli, cabbage, etc.) — they all cross.

Frequently Asked Questions

When should I plant Kale in Hubbard County, MN?

Hubbard County is in Zone 3b with an average last frost of May 12. Plan your Kale planting based on this frost date — see the calendar above for exact timing.

What planting zone is Hubbard County, MN?

Hubbard County, Minnesota is in USDA Hardiness Zone 3b. The average last spring frost is May 12 and first fall frost is September 27.

🌱

Your Hubbard County Garden Planner — Free

A 24-page printable planner built for Hubbard County (Zone 3b). 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 Hubbard County, MN. 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.