When to plant Black-eyed Susan in Washington County County,
Plant Black-eyed Susan in Washington County County, when soil hits 50°F — usually April 21. Continue planting through May 12 for the spring crop.
When to Plant Black-eyed Susan in Washington County, KS
June to-do list for Washington County, Kansas
Here's what deserves your attention in Washington County, Kansas this month. Everything below is tailored to Zone 6a and timed around your local frost dates.
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Fire up the seed-starting tray: black-eyed susan
Label every cell. You will absolutely forget which is which otherwise.
Looking ahead to 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.
Washington County, Kansas is in USDA Zone 6a. The average last spring frost is April 21 and the first fall frost is October 14, giving you a growing season of approximately 176 days.
At an elevation of 562 feet, Washington County receives approximately 26.9 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Black-eyed Susan to ensure they mature before fall.
Washington County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.6
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 Washington County
How your county's soil matches Black-eyed Susan's growing requirements.
Soil pH
Your soil pH (6.8–7.6) is more alkaline than Black-eyed Susan prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Washington County is excellent for Black-eyed Susan — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.4%). Annual compost additions will help Black-eyed Susan.
How to Plant Black-eyed Susan
Succession Planting Black-eyed Susan
Sow every 6.9 weeks. Last sowing by Jul 26 to harvest before frost.
Black-eyed Susan Water Budget
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 | — | 0.8" | 0" | ❄️ Dormant |
| Feb | — | 0.9" | 0" | ❄️ Dormant |
| Mar | — | 1.6" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.2" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.1" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.5" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 2.4" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 1.7" | 0.5" | 💧 Light watering |
| Nov | — | 1" | 0" | ❄️ Dormant |
| Dec | — | 0.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Washington 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 — Washington County, KS
Black-eyed Susan Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 17 | Feb 17 – Mar 3 |
| Transplant Outdoors | April 28 | Apr 28 – May 12 |
| Direct Sow | April 21 | Apr 21 – May 12 |
| Bloom | July 14 | Jul 14 – Oct 27 |
· 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| 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: too_alkaline
🗺️ USDA Zone
Zone 6a
📆 Growing Season
176 days in Washington County
Growing Tips for Black-eyed Susan in Washington County
Direct sow Black-eyed Susan outdoors after April 21 in Washington 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 Washington County, KS?
Washington County is in Zone 6a with an average last frost of April 21. Plan your Black-eyed Susan planting based on this frost date — see the calendar above for exact timing.
What planting zone is Washington County, KS?
Washington County, Kansas is in USDA Hardiness Zone 6a. The average last spring frost is April 21 and first fall frost is October 14.
When should I plant Black-eyed Susan in Washington County County, ?
In Washington County County, , plant Black-eyed Susan after the last frost (around April 21) and before the first frost (around October 14). Best results when soil holds above 50°F.
What growing zone is Washington County County, for Black-eyed Susan?
Washington 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 Washington County County's climate?
Yes — Black-eyed Susan grows well in Washington County County's temperate climate. Washington County County averages a 176-day frost-free season, with last frost around April 21 and first frost around October 14.
Your Washington County Garden Planner — Free
A 22-page printable planner built for Washington 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.