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When to Plant Amaranth in Jackson County, MN

Jackson County, Minnesota Zone 5a May

This month in Jackson County, Minnesota

May is a pivotal month for Jackson County, Minnesota gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost April 30
Avg. first frost October 6
Soil temp (4") 56°F
Watering Low
Pest pressure Low
Daylight 14.5 hrs
  1. Transplant amaranth outside

    Frost risk is low now in Jackson County, Minnesota. If you've been covering beds overnight, you can stop.

  2. Plant amaranth from seed, right in the garden

    Succession planting is the secret here. Put in a row now, another in 2 weeks, a third in 4.

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

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Amaranth is an ancient grain crop with edible leaves and seeds, rich in protein and micronutrients. It thrives in warm conditions and is drought-tolerant once established.

Jackson County, Minnesota is in USDA Zone 5a. The average last spring frost is April 30 and the first fall frost is October 6, giving you a growing season of approximately 159 days.

At an elevation of 1,042 feet, Jackson County receives approximately 37.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Amaranth to ensure they mature before fall.

Jackson County, MN (Zone 5a) Moderate season
159 days
Last Spring Frost April 30
159 growing days
First Fall Frost October 6

Jackson County Soil Profile

Soil Type

Silt Loam

Soil pH

6.1-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (9 days to spare)
Start indoors: Feb 25 Transplant: May 6 🍅 Harvest: Aug 5 – Sep 23
Recommended (50%) ✓ Fits season (5 days to spare)
Start indoors: Mar 5 Transplant: May 14 🍅 Harvest: Aug 13 – Oct 1
Safe Start (90%) ✓ Fits season (6 days to spare)
Start indoors: Mar 19 Transplant: May 28 🍅 Harvest: Aug 27 – Oct 15

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 Jackson County

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

Soil pH

Your soil pH (6.1–7.0) is within Amaranth's preferred range (6.0–7.5).

Soil Texture

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

Organic Matter

Organic matter is excellent (4.2%) — Amaranth will thrive.

How to Plant Amaranth

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
You supply
0.0″/week
Watering frequency Only during dry spells
Season total 10 gal / 100 sq ft

Monthly Watering Guide for Amaranth

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

Month Amaranth Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.3" 0" ❄️ Dormant
Apr 4.3" 3.5" 0.8" 💧 Light watering
May 4.3" 4.6" 0" ✅ Rainfall sufficient
Jun 4.3" 4.7" 0" ✅ Rainfall sufficient
Jul 4.3" 4.5" 0" ✅ Rainfall sufficient
Aug 4.3" 3.6" 0.7" 💧 Light watering
Sep 4.3" 3.2" 1.1" 💧 Light watering
Oct 4.3" 3.1" 1.2" 💧 Light watering
Nov 2.9" 0" ❄️ Dormant
Dec 2" 0" ❄️ Dormant

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

Amaranth 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.

Amaranth needs ~1,050 GDD — county provides 1,590 GDD Excellent fit

Amaranth Planting Timeline — Jackson County, MN

Amaranth Planting Calendar

Activity When Date Range
Start Indoors March 5 Mar 5 – Mar 19
Transplant Outdoors May 14 May 14 – May 28
Direct Sow May 7 May 7 – May 28
Harvest August 13 Aug 13 – Oct 1

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

90–120 days

🧪 Soil pH

Needs 6–7.5 · Your soil: ideal

🗺️ USDA Zone

Zone 5a

📆 Growing Season

159 days in Jackson County

Growing Tips for Amaranth in Jackson County

Direct sow Amaranth outdoors after April 30 in Jackson County when soil has warmed and frost danger has passed.

General growing tips

Direct sow after last frost when soil is warm. Thin seedlings to 18 inches apart. Harvest leaves when young and tender; harvest seeds when flower heads begin to dry.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Amaranth in Jackson County, MN?

Jackson County is in Zone 5a with an average last frost of April 30. Plan your Amaranth planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jackson County, MN?

Jackson County, Minnesota is in USDA Hardiness Zone 5a. The average last spring frost is April 30 and first fall frost is October 6.

🌱

Your Jackson County Garden Planner — Free

A 24-page printable planner built for Jackson 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 Jackson 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.