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When to Plant Tomatoes in Kittson County, MN

Kittson County, Minnesota Zone 3b May

Your May game plan for Kittson County, Minnesota

Here's what deserves your attention in Kittson County, Minnesota this month. Everything below is tailored to Zone 3b and timed around your local frost dates.

Avg. last frost May 14
Avg. first frost September 30
Soil temp (4") 50°F
Watering Low
Pest pressure Low
Daylight 15 hrs
  1. Direct-sow tomatoes

    Sow every 2 weeks for a continuous harvest. A single big planting means a single big glut.

June prep starts now
  • Transplants going out: tomatoes

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Tomatoes are the most popular home garden crop, available in thousands of varieties from tiny cherries to massive beefsteaks. They are warm-season plants needing full sun.

Kittson County, Minnesota is in USDA Zone 3b. The average last spring frost is May 14 and the first fall frost is September 30, giving you a growing season of approximately 139 days.

At an elevation of 778 feet, Kittson County receives approximately 40.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 78°F, so choose short-season varieties of Tomatoes to ensure they mature before fall.

Kittson County, MN (Zone 3b) Short season
139 days
Last Spring Frost May 14
139 growing days
First Fall Frost September 30

Kittson County Soil Profile

Soil Type

Silt Loam

Soil pH

6.2-7.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Mar 7 Transplant: May 30 🍅 Harvest: Aug 1 – Oct 3
Recommended (50%) ✗ May not fit
Start indoors: Mar 12 Transplant: Jun 4 🍅 Harvest: Aug 6 – Oct 8
Safe Start (90%) ✗ May not fit
Start indoors: Mar 28 Transplant: Jun 20 🍅 Harvest: Aug 22 – Oct 24

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 Kittson County

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

Soil pH

Your soil pH (6.2–7.3) overlaps with Tomatoes's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.8%) — Tomatoes will thrive.

How to Plant Tomatoes

0.5"
Planting Depth
24"
Between Plants
36"
Between Rows

Succession Planting Tomatoes

2
successive plantings in your 139-day season

Sow every 6.9 weeks. Last sowing by Jul 07 to harvest before frost.

Plant Water Budget

Plant needs
1.2″/week
Rainfall provides
1.2″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Tomatoes

Tomatoes needs approximately 1.2 inches of water per week (5.2" per month). Here's how your county's rainfall compares month by month.

Month Tomatoes Needs Rainfall You Supplement Action
Jan 1.8" 0" ❄️ Dormant
Feb 2" 0" ❄️ Dormant
Mar 3.1" 0" ❄️ Dormant
Apr 3.6" 0" ❄️ Dormant
May 5.2" 4.5" 0.7" 💧 Light watering
Jun 5.2" 5.3" 0" ✅ Rainfall sufficient
Jul 5.2" 4" 1.2" 💧 Light watering
Aug 5.2" 4.2" 1" 💧 Light watering
Sep 5.2" 3.3" 1.9" 💧 Light watering
Oct 3.4" 0" ❄️ Dormant
Nov 2.9" 0" ❄️ Dormant
Dec 2.1" 0" ❄️ Dormant

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

Tomatoes 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.

Tomatoes needs ~616 GDD — county provides 1,181 GDD Excellent fit

Tomatoes Planting Timeline — Kittson County, MN

Tomatoes Planting Calendar

Activity When Date Range
Start Indoors March 12 Mar 12 – Mar 26
Transplant Outdoors June 4 Jun 4 – Jun 18
Direct Sow May 28 May 28 – Jun 18
Harvest August 6 Aug 6 – Oct 8

Plant 0.5" deep · 24" apart · Rows 36" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.2"/week · Natural rainfall sufficient

📅 Days to Maturity

60–85 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 3b

📆 Growing Season

139 days in Kittson County

Growing Tips for Tomatoes in Kittson County

Direct sow Tomatoes outdoors after May 14 in Kittson County when soil has warmed and frost danger has passed.

Common pests for Tomatoes in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors 6-8 weeks before last frost. Bury transplants deep to encourage rooting along the stem. Provide consistent moisture to prevent blossom end rot and cracking.

Recommended Tomatoes Varieties for Kittson County

Choose determinate, early-maturing varieties for your short season

Early Girl (52d) Stupice (55d) Glacier (55d) Sub Arctic Plenty (45d)

Companion Planting

Good Companions

Avoid Planting Near

  • Cabbage
  • Fennel
  • Potatoes

Check more plant combinations with our Companion Planting Checker →

🌾 Save Your Own Tomatoes Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Scoop seeds from ripe fruit; ferment 2-3 days to remove gel coating.
Storage Store airtight; viable 4-6 years at 35°F, under 45% humidity.

Isolate 25 ft between varieties for purity. Use open-pollinated varieties for true-to-type seeds.

Frequently Asked Questions

When should I plant Tomatoes in Kittson County, MN?

Kittson County is in Zone 3b with an average last frost of May 14. Plan your Tomatoes planting based on this frost date — see the calendar above for exact timing.

What planting zone is Kittson County, MN?

Kittson County, Minnesota is in USDA Hardiness Zone 3b. The average last spring frost is May 14 and first fall frost is September 30.

🌱

Your Kittson County Garden Planner — Free

A 24-page printable planner built for Kittson 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.

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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 Kittson 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.