When to plant Black-eyed Susan in Lee County County,
The best window to plant Black-eyed Susan in Lee County County, is April 16–May 7, when soil warms to 50°F. Last frost typically hits April 16; first frost October 18.
When to Plant Black-eyed Susan in Lee County, IA
Top priorities for Lee County, Iowa gardeners in June
Your Lee County, Iowa garden is entering a new phase. Here's what's on the schedule for June and why each task matters now.
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Begin indoor sowing: black-eyed susan
Give them 6–8 weeks indoors before the last frost and you'll transplant into warm soil with seedlings that are already leaping.
A few tasks this June that'll pay off in July
- First harvests: black-eyed susan
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.
Lee County, Iowa is in USDA Zone 6a. The average last spring frost is April 16 and the first fall frost is October 18, giving you a growing season of approximately 185 days.
At an elevation of 1,393 feet, Lee County receives approximately 36.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Black-eyed Susan to ensure they mature before fall.
Lee County Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-7.2
Drainage
Well Drained
Black-eyed Susan Planting Risk Windows
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 Lee County
How your county's soil matches Black-eyed Susan's growing requirements.
Soil pH
Your soil pH (6.1–7.2) overlaps with Black-eyed Susan's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Lee County is excellent for Black-eyed Susan — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Black-eyed Susan.
Organic Matter
Organic matter is excellent (4.4%) — Black-eyed Susan will thrive.
How to Plant Black-eyed Susan
Succession Planting Black-eyed Susan
Sow every 6.9 weeks. Last sowing by Jul 30 to harvest before frost.
Black-eyed Susan Water Budget
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 | — | 1.8" | 0" | ❄️ Dormant |
| Mar | — | 2.9" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4.2" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 4" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 4.1" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 2.9" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 2.9" | 0" | ✅ Rainfall sufficient |
| Nov | — | 3" | 0" | ❄️ Dormant |
| Dec | — | 1.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Lee 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 Planting Timeline — Lee County, IA
Black-eyed Susan Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 12 | Feb 12 – Feb 26 |
| Transplant Outdoors | April 23 | Apr 23 – May 7 |
| Direct Sow | April 16 | Apr 16 – May 7 |
| Bloom | July 9 | Jul 9 – Oct 22 |
· 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | — |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Bloom |
| 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 6a
📆 Growing Season
185 days in Lee County
Growing Tips for Black-eyed Susan in Lee County
Direct sow Black-eyed Susan outdoors after April 16 in Lee 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.
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 →
Black-eyed Susan in Other Locations
Frequently Asked Questions
When should I plant Black-eyed Susan in Lee County, IA?
Lee County is in Zone 6a with an average last frost of April 16. Plan your Black-eyed Susan planting based on this frost date — see the calendar above for exact timing.
What planting zone is Lee County, IA?
Lee County, Iowa is in USDA Hardiness Zone 6a. The average last spring frost is April 16 and first fall frost is October 18.
When should I plant Black-eyed Susan in Lee County County, ?
In Lee County County, , plant Black-eyed Susan after the last frost (around April 16) and before the first frost (around October 18). Best results when soil holds above 50°F.
What growing zone is Lee County County, for Black-eyed Susan?
Lee County County sits in USDA Zone 6a. Black-eyed Susan grows reliably in zones 3a through 9b, so it's a good fit here.
Can Black-eyed Susan grow in Lee County County's climate?
Yes — Black-eyed Susan grows well in Lee County County's temperate climate. Lee County County averages a 185-day frost-free season, with last frost around April 16 and first frost around October 18.
Your Lee County Garden Planner — Free
A 22-page printable planner built for Lee County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.