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When to Plant Astilbe in Dickson County, TN

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.

Dickson County, Tennessee is in USDA Zone 7b. The average last spring frost is April 4 and the first fall frost is October 29, giving you a growing season of approximately 208 days.

At an elevation of 2,147 feet, Dickson County receives approximately 54 inches of rainfall annually with predominantly silt loam soil. Summer highs average 92°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.

Perennial Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting
Dickson County, TN (Zone 7b) Long season
208 days
Last Spring Frost April 4
208 growing days
First Fall Frost October 29

Dickson County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Astilbe Planting Timeline — Dickson County, TN

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

MonthActivities
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 7b

📆 Growing Season

208 days in Dickson County

Growing Tips for Dickson 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 →

Frequently Asked Questions

When should I plant Astilbe in Dickson County, TN?

Dickson County is in Zone 7b 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 Dickson County, TN?

Dickson County, Tennessee is in USDA Hardiness Zone 7b. The average last spring frost is April 4 and first fall frost is October 29.

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A 22-page printable planner built for Dickson County (Zone 7b). 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 Dickson County, TN. Local conditions may vary. Last updated: June 2026.

Sources & credits

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