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When to Plant Turnip in Rock County, MN

Rock County, Minnesota Zone 5a May

May in the garden — Rock County, Minnesota

We've pulled the most time-sensitive tasks for Rock County, Minnesota this May and put them front and centre. Tackle them in order.

Avg. last frost May 2
Avg. first frost October 2
Soil temp (4") 53°F
Watering Moderate
Pest pressure Low
Daylight 14.5 hrs
  1. Basket week: turnip

    Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.

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  • First harvests: turnip

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Turnips are a fast-growing cool-season root vegetable with edible roots and greens. Baby turnips are sweet and tender while mature ones are more pungent.

Rock County, Minnesota is in USDA Zone 5a. The average last spring frost is May 2 and the first fall frost is October 2, giving you a growing season of approximately 153 days.

At an elevation of 916 feet, Rock County receives approximately 32.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Turnip to ensure they mature before fall.

Rock County, MN (Zone 5a) Moderate season
153 days
Last Spring Frost May 2
153 growing days
First Fall Frost October 2
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Rock County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (74 days to spare)
Transplant: Apr 27 🍅 Harvest: Jun 8 – Jul 13
Recommended (50%) ✓ Fits season (76 days to spare)
Transplant: May 2 🍅 Harvest: Jun 13 – Jul 18
Safe Start (90%) ✓ Fits season (73 days to spare)
Transplant: May 16 🍅 Harvest: Jun 27 – Aug 1

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 Rock County

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

Soil pH

Your soil pH (5.7–6.9) overlaps with Turnip's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (5.1%) — Turnip will thrive.

How to Plant Turnip

0.5"
Planting Depth
4"
Between Plants
12"
Between Rows

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

Succession Planting Turnip

4
successive plantings in your 153-day season

Sow every 4.6 weeks. Last sowing by Aug 03 to harvest before frost.

For a dedicated fall crop, sow by Jul 24.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 181 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Turnip

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

Month Turnip Needs Rainfall You Supplement Action
Jan 1.2" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 2.4" 0" ❄️ Dormant
Apr 2.9" 0" ❄️ Dormant
May 4.3" 3.3" 1" 💧 Light watering
Jun 4.3" 4.2" 0.1" 💧 Light watering
Jul 4.3" 4.1" 0.2" 💧 Light watering
Aug 4.3" 3.5" 0.8" 💧 Light watering
Sep 4.3" 2.7" 1.6" 💧 Light watering
Oct 4.3" 2.5" 1.8" 💧 Light watering
Nov 2.4" 0" ❄️ Dormant
Dec 1.7" 0" ❄️ Dormant

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

Turnip 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.

Turnip needs ~575 GDD — county provides 1,759 GDD Excellent fit

Turnip Planting Timeline — Rock County, MN

Turnip Planting Calendar

Activity When Date Range
Direct Sow April 18 Apr 18 – May 9
Harvest May 30 May 30 – Jul 4
Fall Sowing July 24 Jul 24 – Aug 7

Plant 0.5" deep · 4" apart · Rows 12" apart

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

40–60 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 5a

📆 Growing Season

153 days in Rock County

Growing Tips for Turnip in Rock County

Direct sow Turnip outdoors after May 02 in Rock County when soil has warmed and frost danger has passed.

Your generous 153.0-day season in Rock County allows multiple plantings of Turnip. Sow every 20.0 days for continuous harvest.

Common pests for Turnip 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 early spring or late summer. Harvest when roots are 2-3 inches in diameter for best flavor. Both the roots and the greens are nutritious and edible.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Turnip in Rock County, MN?

Rock County is in Zone 5a with an average last frost of May 2. Plan your Turnip planting based on this frost date — see the calendar above for exact timing.

What planting zone is Rock County, MN?

Rock County, Minnesota is in USDA Hardiness Zone 5a. The average last spring frost is May 2 and first fall frost is October 2.

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Your Rock County Garden Planner — Free

A 24-page printable planner built for Rock 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 Rock 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.