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When to plant Astilbe in Elk County, KS

Elk County's short 201-day growing season means one Astilbe planting between April 14 and April 28. No fall crop in Zone 7a.

When to Plant Astilbe in Elk County, KS

Elk County, Kansas Zone 7a June

Elk County, Kansas gardeners: here's your June plan

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

Avg. last frost April 7
Avg. first frost October 25
Soil temp (4") 74°F
Watering Low
Pest pressure High
Daylight 14.6 hrs
  1. Time to start astilbe inside

    Your window is short. These crops want several weeks of indoor growth before they go outside.

  2. Bring in the astilbe

    Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.

Get ahead of 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.

Elk County, Kansas is in USDA Zone 7a. The average last spring frost is April 7 and the first fall frost is October 25, giving you a growing season of approximately 201 days.

At an elevation of 700 feet, Elk County receives approximately 30.4 inches of rainfall annually with predominantly loam soil. Summer highs average 90°F, providing good warmth for Astilbe during the growing season.

Perennial Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting
Elk County, KS (Zone 7a) Long season
201 days
Last Spring Frost April 7
201 growing days
First Fall Frost October 25

Elk County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.6

Drainage

Well Drained

Astilbe Planting Risk Windows

Early Start (70% safe) ✓ Fits season (70 days to spare)
Start indoors: Jan 26 Transplant: Apr 6 🌸 Bloom: Jun 15 – Aug 10
Recommended (50%) ✓ Fits season (68 days to spare)
Start indoors: Feb 3 Transplant: Apr 14 🌸 Bloom: Jun 23 – Aug 18
Safe Start (90%) ✓ Fits season (70 days to spare)
Start indoors: Feb 17 Transplant: Apr 28 🌸 Bloom: Jul 7 – Sep 1

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 Elk County

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

Soil pH

Your soil pH (6.8–7.6) is within Astilbe's preferred range (6.0–8.0).

Soil Texture

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

Organic Matter

Organic matter is excellent (4.1%) — Astilbe will thrive.

How to Plant Astilbe

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

Succession Planting Astilbe

3
successive plantings in your 201-day season

Sow every 8 weeks. Last sowing by Jul 17 to harvest before frost.

Astilbe Water Budget

Plant needs
1.5″/week
Rainfall provides
0.6″/week
You supply
1.0″/week
Watering frequency 2-3 times/week
Season total 1,856 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 0.9" 0" ❄️ Dormant
Feb 0.9" 0" ❄️ Dormant
Mar 2.1" 0" ❄️ Dormant
Apr 6.5" 3" 3.5" 🚿 Regular watering
May 6.5" 4.7" 1.8" 💧 Light watering
Jun 6.5" 4.6" 1.9" 💧 Light watering
Jul 6.5" 3.5" 3" 💧 Light watering
Aug 6.5" 3.7" 2.8" 💧 Light watering
Sep 6.5" 3.2" 3.3" 🚿 Regular watering
Oct 6.5" 2.1" 4.4" 🚿 Regular watering
Nov 1.1" 0" ❄️ Dormant
Dec 0.7" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Elk 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 ~1,488 GDD — county provides 3,517 GDD Excellent fit

Astilbe Planting Timeline — Elk County, KS

Astilbe Planting Calendar

Activity When Date Range
Start Indoors February 3 Feb 3 – Feb 17
Transplant Outdoors April 14 Apr 14 – Apr 28
Bloom June 23 Jun 23 – Aug 18

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

Month-by-Month Timeline

MonthActivities
January
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

1.5"/week · 2-3 times/week

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–8 · Your soil: ideal

🗺️ USDA Zone

Zone 7a

📆 Growing Season

201 days in Elk County

Growing Tips for Astilbe in Elk County

Direct sow Astilbe outdoors after April 07 in Elk 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 Elk County, KS?

Elk County is in Zone 7a with an average last frost of April 7. Plan your Astilbe planting based on this frost date — see the calendar above for exact timing.

What planting zone is Elk County, KS?

Elk County, Kansas is in USDA Hardiness Zone 7a. The average last spring frost is April 7 and first fall frost is October 25.

When should I plant Astilbe in Elk County, KS?

In Elk County, KS, plant Astilbe after the last frost (around April 7) and before the first frost (around October 25). Best results when soil holds above 50°F.

What growing zone is Elk County, KS for Astilbe?

Elk 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 Elk County's climate?

Yes — Astilbe grows well in Elk County's temperate climate. Elk County averages a 201-day frost-free season, with last frost around April 7 and first frost around October 25.

🌱

Your Elk County Garden Planner — Free

A 22-page printable planner built for Elk 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.

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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 Elk County, KS. 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.