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When to Plant Black-eyed Susan in Sheridan County, ND

Sheridan County, North Dakota Zone 4a June

June in the garden — Sheridan County, North Dakota

June is a pivotal month for Sheridan County, North Dakota gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost May 12
Avg. first frost October 1
Soil temp (4") 61°F
Watering High
Pest pressure Moderate
Daylight 15.7 hrs
To set up a strong July, finish these tasks
  • Starting indoors: black-eyed susan

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Rudbeckia hirta (Black-eyed Susan) is one of the most recognizable and adaptable native wildflowers in North America. Its bright golden-yellow daisy petals radiate from a dark brown central cone, providing months of color from midsummer into fall. Technically a short-lived perennial that self-seeds freely — colonies persist indefinitely in the garden — it thrives in poor soils, tolerates drought, and is irresistible to bees, butterflies, and goldfinches.

Sheridan County, North Dakota is in USDA Zone 4a. The average last spring frost is May 12 and the first fall frost is October 1, giving you a growing season of approximately 142 days.

At an elevation of 1,070 feet, Sheridan County receives approximately 24.1 inches of rainfall annually with predominantly loam soil. Summer highs average 81°F, so choose short-season varieties of Black-eyed Susan to ensure they mature before fall.

Perennial Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting
Sheridan County, ND (Zone 4a) Short season
142 days
Last Spring Frost May 12
142 growing days
First Fall Frost October 1

Sheridan County Soil Profile

Soil Type

Loam

Soil pH

6.4-7.5

Drainage

Well Drained

Black-eyed Susan Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Feb 23 Transplant: May 18 🌸 Bloom: Aug 10 – Oct 19
Recommended (50%) ✗ May not fit
Start indoors: Mar 3 Transplant: May 26 🌸 Bloom: Aug 18 – Oct 27
Safe Start (90%) ✗ May not fit
Start indoors: Mar 11 Transplant: Jun 3 🌸 Bloom: Aug 26 – Nov 4

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 Sheridan County

How your county's soil matches Black-eyed Susan's growing requirements.

Soil pH

Your soil pH (6.4–7.5) overlaps with Black-eyed Susan's range (6.0–7.0), though not a perfect match.

Soil Texture

The loam soil in Sheridan County is excellent for Black-eyed Susan — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.5%). Annual compost additions will help Black-eyed Susan.

How to Plant Black-eyed Susan

18"
Between Plants
24"
Between Rows

Succession Planting Black-eyed Susan

2
successive plantings in your 142-day season

Sow every 6.9 weeks. Last sowing by Jul 13 to harvest before frost.

Black-eyed Susan Water Budget

Plant needs
0.5″/week
Rainfall provides
0.7″/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 Black-eyed Susan

Black-eyed Susan 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 Black-eyed Susan Needs Rainfall You Supplement Action
Jan 1.7" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 2" 0" ❄️ Dormant
Apr 2.4" 0" ❄️ Dormant
May 2.2" 2.7" 0" ✅ Rainfall sufficient
Jun 2.2" 1.7" 0.5" 💧 Light watering
Jul 2.2" 2.4" 0" ✅ Rainfall sufficient
Aug 2.2" 2.2" 0" ✅ Rainfall sufficient
Sep 2.2" 1.9" 0.3" 💧 Light watering
Oct 2.2" 2.1" 0.1" 💧 Light watering
Nov 1.9" 0" ❄️ Dormant
Dec 1.6" 0" ❄️ Dormant

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

Black-eyed Susan 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.

Black-eyed Susan needs ~752 GDD — county provides 1,526 GDD Excellent fit

Black-eyed Susan Planting Timeline — Sheridan County, ND

Black-eyed Susan Planting Calendar

Activity When Date Range
Start Indoors March 3 Mar 3 – Mar 17
Transplant Outdoors May 26 May 26 – Jun 9
Direct Sow May 12 May 12 – Jun 2
Bloom August 18 Aug 18 – Oct 27

· 18" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April
May Transplant Outdoors Direct Sow
June Transplant Outdoors 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

60–80 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 4a

📆 Growing Season

142 days in Sheridan County

Growing Tips for Black-eyed Susan in Sheridan County

Direct sow Black-eyed Susan outdoors after May 12 in Sheridan County when soil has warmed and frost danger has passed.

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

Sheridan County receives only 24" of rain annually. Black-eyed Susan needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Start seeds indoors 8–10 weeks before last frost or direct-sow after last frost (needs light to germinate — press seeds onto soil surface, do not cover). Thrives in average to poor soil; rich soil causes floppy stems. Deadhead for extended bloom but leave some seed heads for winter wildlife interest and self-seeding. Although technically short-lived (3–5 years), prolific self-seeding maintains the colony. Year 2+ plants bloom most heavily. Divide every 3 years to maintain vigor.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Black-eyed Susan in Sheridan County, ND?

Sheridan County is in Zone 4a with an average last frost of May 12. Plan your Black-eyed Susan planting based on this frost date — see the calendar above for exact timing.

What planting zone is Sheridan County, ND?

Sheridan County, North Dakota is in USDA Hardiness Zone 4a. The average last spring frost is May 12 and first fall frost is October 1.

🌱

Your Sheridan County Garden Planner — Free

A 22-page printable planner built for Sheridan County (Zone 4a). 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 Sheridan County, ND. Local conditions may vary. Last updated: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.