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When to plant Astilbe in Sevier County, AR

In Sevier County, Astilbe is a spring-only crop. Plant March 25–April 8 once soil hits 50°F.

When to Plant Astilbe in Sevier County, AR

Sevier County, Arkansas Zone 8a June

June in Sevier County, Arkansas — your action list

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

Avg. last frost March 25
Avg. first frost November 6
Soil temp (4") 80°F
Watering Low
Pest pressure High
Daylight 14.3 hrs
  1. Basket week: astilbe

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

Looking ahead to July
  • First harvests: astilbe

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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.

Sevier County, Arkansas is in USDA Zone 8a. The average last spring frost is March 25 and the first fall frost is November 6, giving you a growing season of approximately 226 days.

At an elevation of 845 feet, Sevier County receives approximately 49.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Astilbe during the growing season.

Perennial Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting
Sevier County, AR (Zone 8a) Long season
226 days
Last Spring Frost March 25
226 growing days
First Fall Frost November 6

Sevier County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.5

Drainage

Well Drained

Astilbe Planting Risk Windows

Early Start (70% safe) ✓ Fits season (110 days to spare)
Start indoors: Jan 19 Transplant: Mar 16 🌸 Bloom: May 25 – Jul 13
Recommended (50%) ✓ Fits season (107 days to spare)
Start indoors: Jan 28 Transplant: Mar 25 🌸 Bloom: Jun 3 – Jul 22
Safe Start (90%) ✓ Fits season (105 days to spare)
Start indoors: Feb 18 Transplant: Apr 15 🌸 Bloom: Jun 24 – Aug 12

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 Sevier County

How your county's soil matches Astilbe's growing requirements.

Soil pH

Your soil pH (5.4–6.5) is more acidic than Astilbe prefers (6.0–8.0). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Sevier County is excellent for Astilbe — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Astilbe.

Organic Matter

Organic matter is moderate (2.6%). Annual compost additions will help Astilbe.

How to Plant Astilbe

1.5"
Planting Depth
18"
Between Plants
24"
Between Rows

Succession Planting Astilbe

3
successive plantings in your 226-day season

Sow every 8 weeks. Last sowing by Jul 29 to harvest before frost.

Astilbe Water Budget

Plant needs
1.5″/week
Rainfall provides
0.9″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 305 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Astilbe

Astilbe needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.

Month Astilbe Needs Rainfall You Supplement Action
Jan 3.9" 0" ❄️ Dormant
Feb 4.2" 0" ❄️ Dormant
Mar 6.5" 4.3" 2.2" 💧 Light watering
Apr 6.5" 4.2" 2.3" 💧 Light watering
May 6.5" 4.1" 2.4" 💧 Light watering
Jun 6.5" 5" 1.5" 💧 Light watering
Jul 6.5" 4.6" 1.9" 💧 Light watering
Aug 6.5" 5.1" 1.4" 💧 Light watering
Sep 6.5" 3.5" 3" 💧 Light watering
Oct 6.5" 2.7" 3.8" 🚿 Regular watering
Nov 6.5" 4.1" 2.4" 💧 Light watering
Dec 3.8" 0" ❄️ Dormant

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

Astilbe 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.

Astilbe needs ~1,424 GDD — county provides 3,785 GDD Excellent fit

Astilbe Planting Timeline — Sevier County, AR

Astilbe Planting Calendar

Activity When Date Range
Start Indoors January 28 Jan 28 – Feb 11
Transplant Outdoors March 25 Mar 25 – Apr 8
Bloom June 3 Jun 3 – Jul 22

Plant 1.5" deep · 18" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January Start Indoors
February Start Indoors
March Transplant Outdoors
April Transplant Outdoors
May
June Bloom
July Bloom
August
September
October
November
December

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1.5"/week · Only during dry spells

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–8 · Your soil: too_acidic

🗺️ USDA Zone

Zone 8a

📆 Growing Season

226 days in Sevier County

Growing Tips for Astilbe in Sevier County

Direct sow Astilbe outdoors after March 25 in Sevier County when soil has warmed and frost danger has passed.

General growing tips

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 Sevier County, AR?

Sevier County is in Zone 8a with an average last frost of March 25. Plan your Astilbe planting based on this frost date — see the calendar above for exact timing.

What planting zone is Sevier County, AR?

Sevier County, Arkansas is in USDA Hardiness Zone 8a. The average last spring frost is March 25 and first fall frost is November 6.

When should I plant Astilbe in Sevier County, AR?

In Sevier County, AR, plant Astilbe after the last frost (around March 25) and before the first frost (around November 6). Best results when soil holds above 50°F.

What growing zone is Sevier County, AR for Astilbe?

Sevier County sits in USDA Zone 8a. Astilbe grows reliably in zones 3a through 8b, so it's a good fit here.

Can Astilbe grow in Sevier County's climate?

Yes — Astilbe grows well in Sevier County's temperate climate. Sevier County averages a 226-day frost-free season, with last frost around March 25 and first frost around November 6.

🌱

Your Sevier County Garden Planner — Free

A 22-page printable planner built for Sevier County (Zone 8a). 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 Sevier County, AR. 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.