When to plant Astilbe in Kit Carson County County,
In Kit Carson County County, Astilbe is a single-season spring crop — there's no second fall window. Plant May 16–May 30 for an 100-day harvest, finishing well before the October 8 first frost.
When to Plant Astilbe in Kit Carson County, CO
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.
Kit Carson County, Colorado is in USDA Zone 6a. The average last spring frost is May 9 and the first fall frost is October 8, giving you a growing season of approximately 152 days.
At an elevation of 6,382 feet, Kit Carson County receives approximately 23.2 inches of rainfall annually with predominantly loam soil. Summer highs average 85°F, providing good warmth for Astilbe during the growing season.
Kit Carson County Soil Profile
Soil Type
Loam
Soil pH
6.4-8
Drainage
Well Drained
Monthly Watering Guide for Astilbe
Astilbe needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Astilbe Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.4" | 0" | ❄️ Dormant |
| Mar | — | 2.2" | 0" | ❄️ Dormant |
| Apr | — | 2.4" | 0" | ❄️ Dormant |
| May | 4.3" | 2.8" | 1.5" | 💧 Light watering |
| Jun | 4.3" | 1.4" | 2.9" | 🚿 Regular watering |
| Jul | 4.3" | 2.2" | 2.1" | 💧 Light watering |
| Aug | 4.3" | 2.7" | 1.6" | 💧 Light watering |
| Sep | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Oct | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Nov | — | 1.5" | 0" | ❄️ Dormant |
| Dec | — | 1.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Kit Carson County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Astilbe Planting Timeline — Kit Carson County, CO
Astilbe Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 7 | Mar 7 – Mar 21 |
| Transplant Outdoors | May 16 | May 16 – May 30 |
| Bloom | July 25 | Jul 25 – Oct 3 |
Plant 1.5" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| 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 6a
📆 Growing Season
152 days in Kit Carson County
Growing Tips for Kit Carson 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 Kit Carson County, CO?
Kit Carson County is in Zone 6a with an average last frost of May 9. Plan your Astilbe planting based on this frost date — see the calendar above for exact timing.
What planting zone is Kit Carson County, CO?
Kit Carson County, Colorado is in USDA Hardiness Zone 6a. The average last spring frost is May 9 and first fall frost is October 8.
When should I plant Astilbe in Kit Carson County County, ?
In Kit Carson County County, , plant Astilbe after the last frost (around May 9) and before the first frost (around October 8). Best results when soil holds above 50°F.
What growing zone is Kit Carson County County, for Astilbe?
Kit Carson County County sits in USDA Zone 6a. Astilbe grows reliably in zones 3a through 8b, so it's a good fit here.
Can Astilbe grow in Kit Carson County County's climate?
Yes — Astilbe grows well in Kit Carson County County's temperate climate. Kit Carson County County averages a 152-day frost-free season, with last frost around May 9 and first frost around October 8.
Your Kit Carson County Garden Planner — Free
A 22-page printable planner built for Kit Carson 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.