When to plant Astilbe in Larue County, KY
Larue County's short 211-day growing season means one Astilbe planting between April 11 and April 25. No fall crop in Zone 7a.
When to Plant Astilbe in Larue County, KY
Astilbe (Astilbe x arendsii) is a premier perennial for shaded, moist gardens, producing feathery plume-like flower spikes in shades of pink, red, white, and lavender above deeply cut, ferny foliage. Originating in Asia and naturalized in shade gardens worldwide, astilbe thrives where many sun-lovers fail: under trees, beside water features, or in persistently moist woodland borders. The dried flower plumes remain attractive through fall and winter. Different cultivars extend the bloom season from early summer through early fall when several varieties are combined.
Larue County, Kentucky is in USDA Zone 7a. The average last spring frost is April 4 and the first fall frost is November 1, giving you a growing season of approximately 211 days.
At an elevation of 2,923 feet, Larue County receives approximately 52.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Astilbe during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Astilbe root diseases.
Larue County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Astilbe Planting Timeline — Larue County, KY
Astilbe Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 31 | Jan 31 – Feb 14 |
| Transplant Outdoors | April 11 | Apr 11 – Apr 25 |
| Bloom | June 20 | Jun 20 – Aug 15 |
Plant 1.5" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Start Indoors |
| March | — |
| April | Transplant Outdoors |
| May | — |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
High — keep soil consistently moist
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–8 · Your soil: N/A
🗺️ USDA Zone
Zone 7a
📆 Growing Season
211 days in Larue County
Growing Tips for Larue County
Plant bare-root crowns in spring as soon as the ground is workable, setting eyes 1–2 inches below soil level. Fall planting (Zones 4+) is equally effective. Consistent moisture is non-negotiable — astilbe will wilt and scorch in drought. Amend with generous compost to improve moisture retention. Partial shade (morning sun, afternoon shade) is ideal; deep shade reduces bloom but foliage remains. Fertilize lightly in spring with a balanced slow-release granular. Divide every 3–5 years in early spring as clumps become congested. Leave plumes standing through winter for ornamental interest and wildlife value. Year 2+ plants produce the fullest bloom spikes; first-year crowns may flower lightly or not at all.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Astilbe in Other Locations
Frequently Asked Questions
When should I plant Astilbe in Larue County, KY?
Larue County is in Zone 7a with an average last frost of April 4. Plan your Astilbe planting based on this frost date — see the calendar above for exact timing.
What planting zone is Larue County, KY?
Larue County, Kentucky is in USDA Hardiness Zone 7a. The average last spring frost is April 4 and first fall frost is November 1.
When should I plant Astilbe in Larue County, KY?
In Larue County, KY, plant Astilbe after the last frost (around April 4) and before the first frost (around November 1). Best results when soil holds above 50°F.
What growing zone is Larue County, KY for Astilbe?
Larue County sits in USDA Zone 7a. Astilbe grows reliably in zones 3a through 8b, so it's a good fit here.
Can Astilbe grow in Larue County's climate?
Yes — Astilbe grows well in Larue County's temperate climate. Larue County averages a 211-day frost-free season, with last frost around April 4 and first frost around November 1.
Your Larue County Garden Planner — Free
A 22-page printable planner built for Larue County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.