Blog

When to plant Sunflower in Shingleton, MI

Plant Sunflower in Shingleton after May 10; the prime window is May 17–June 7.

When to Plant Sunflower in Shingleton, MI

Alger County, Michigan Zone 5a July

This month in Alger County, Michigan

July rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Alger County, Michigan.

Avg. last frost May 10
Avg. first frost October 16
Soil temp (4") 73°F
Watering Low
Pest pressure High
Daylight 15.3 hrs
Get ahead of August
  • First harvests: sunflower

Instant PDF download. No spam, unsubscribe any time.

Sunflower (Helianthus annuus) is a fast-growing North American native annual famous for its towering stems and brilliant yellow heads. It thrives in full sun and heat, producing large, pollen-rich blooms that attract bees, butterflies, and seed-eating birds. Varieties range from 18-inch dwarfs to 12-foot giants and nearly every color except blue.

Shingleton, Michigan is in USDA Zone 5a. The average last spring frost is May 10 and the first fall frost is October 16, giving you a growing season of approximately 159 days.

At an elevation of 1,014 feet, Alger County receives approximately 40.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Sunflower to ensure they mature before fall.

Annual Blooms in Summer Pollinator-friendly Good for cutting
Shingleton, MI (Zone 5a) Moderate season
159 days
Last Spring Frost May 10
159 growing days
First Fall Frost October 16

Shingleton Soil Profile

Soil Type

Silt Loam

Soil pH

6.3-7.1

Drainage

Well Drained

Sunflower Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Apr 11 Transplant: May 9 🌸 Bloom: Aug 1 – Oct 10
Recommended (50%) ✗ May not fit
Start indoors: Apr 19 Transplant: May 17 🌸 Bloom: Aug 9 – Oct 18
Safe Start (90%) ✓ Fits season (0 days to spare)
Start indoors: May 4 Transplant: Jun 1 🌸 Bloom: Aug 24 – Nov 2

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 Shingleton

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

Soil pH

Your soil pH (6.3–7.1) is within Sunflower's preferred range (6.0–7.5).

Soil Texture

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

Drainage

Drainage is adequate for Sunflower.

Organic Matter

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

How to Plant Sunflower

1"
Planting Depth
18"
Between Plants
24"
Between Rows

Succession Planting Sunflower

2
successive plantings in your 159-day season

Sow every 8 weeks. Last sowing by Jul 08 to harvest before frost.

Sunflower Water Budget

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

Monthly Watering Guide for Sunflower

Sunflower needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Sunflower Needs Rainfall You Supplement Action
Jan 2" 0" ❄️ Dormant
Feb 2" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 3.5" 0" ❄️ Dormant
May 2.2" 4.3" 0" ✅ Rainfall sufficient
Jun 2.2" 5" 0" ✅ Rainfall sufficient
Jul 2.2" 5" 0" ✅ Rainfall sufficient
Aug 2.2" 4.7" 0" ✅ Rainfall sufficient
Sep 2.2" 3.9" 0" ✅ Rainfall sufficient
Oct 2.2" 3" 0" ✅ Rainfall sufficient
Nov 2.9" 0" ❄️ Dormant
Dec 2.1" 0" ❄️ Dormant

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

Sunflower 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.

Sunflower needs ~850 GDD — county provides 1,590 GDD Excellent fit

Sunflower Planting Timeline — Shingleton, MI

Sunflower Planting Calendar

Activity When Date Range
Start Indoors April 19 Apr 19 – May 3
Transplant Outdoors May 17 May 17 – May 31
Direct Sow May 17 May 17 – Jun 7
Bloom August 9 Aug 9 – Oct 18

Plant 1" deep · 18" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7.5 · Your soil: ideal

🗺️ USDA Zone

Zone 5a

📆 Growing Season

159 days in Alger County

Growing Tips for Sunflower in Shingleton

Direct sow Sunflower outdoors after May 10 in Alger County when soil has warmed and frost danger has passed.

Common pests for Sunflower in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct-sow 1 inch deep after last frost; germination takes 7-14 days at 65-75°F soil. Sunflowers dislike root disturbance so direct sowing is strongly preferred over transplanting. Plant in succession every 2 weeks for extended bloom. Stake tall varieties. Avoid overwatering — they tolerate drought once established. Birds will self-deadhead seed heads; leave them up through fall for wildlife.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes
  • Pole_beans

Check more plant combinations with our Companion Planting Checker →

When should I plant Sunflower in Shingleton, MI?

In Shingleton, MI, plant Sunflower after the last frost (around May 10) and before the first frost (around October 16). Best results when soil holds above 50°F.

What growing zone is Shingleton, MI for Sunflower?

Shingleton sits in USDA Zone 5a. Sunflower grows reliably in zones 2a through 11b, so it's a good fit here.

Can Sunflower grow in Shingleton's climate?

Yes — Sunflower grows well in Shingleton's temperate climate. Shingleton averages a 159-day frost-free season, with last frost around May 10 and first frost around October 16.

🌱

Your Alger County Garden Planner — Free

A 22-page printable planner built for Alger 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 Alger County, MI. Local conditions may vary. Last updated: July 2026.