When to plant Astilbe in Hubbard County, MN
In Hubbard County, Astilbe is a spring-only crop. Plant May 26–June 9 once soil hits 50°F.
When to Plant Astilbe in Hubbard County, MN
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.
Hubbard County, Minnesota is in USDA Zone 3b. The average last spring frost is May 12 and the first fall frost is September 27, giving you a growing season of approximately 138 days.
At an elevation of 733 feet, Hubbard County receives approximately 32.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 79°F, so choose short-season varieties of Astilbe to ensure they mature before fall.
Hubbard County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Astilbe Planting Timeline — Hubbard County, MN
Astilbe Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 3 | Mar 3 – Mar 17 |
| Transplant Outdoors | May 26 | May 26 – Jun 9 |
| Bloom | August 18 | Aug 18 – Oct 6 |
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 | Transplant Outdoors |
| July | — |
| 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 3b
📆 Growing Season
138 days in Hubbard County
Growing Tips for Hubbard 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 Hubbard County, MN?
Hubbard County is in Zone 3b with an average last frost of May 12. Plan your Astilbe planting based on this frost date — see the calendar above for exact timing.
What planting zone is Hubbard County, MN?
Hubbard County, Minnesota is in USDA Hardiness Zone 3b. The average last spring frost is May 12 and first fall frost is September 27.
When should I plant Astilbe in Hubbard County, MN?
In Hubbard County, MN, plant Astilbe after the last frost (around May 12) and before the first frost (around September 27). Best results when soil holds above 50°F.
What growing zone is Hubbard County, MN for Astilbe?
Hubbard County sits in USDA Zone 3b. Astilbe grows reliably in zones 3a through 8b, so it's a good fit here.
Can Astilbe grow in Hubbard County's climate?
Yes — Astilbe grows well in Hubbard County's temperate climate. Hubbard County averages a 138-day frost-free season, with last frost around May 12 and first frost around September 27.
Your Hubbard County Garden Planner — Free
A 22-page printable planner built for Hubbard County (Zone 3b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.