When to plant Foxglove in Mahnomen County, MN
Plant Foxglove in Mahnomen County during the brief May 27–June 17 window. With 137 frost-free days, fall plantings can't mature before September 27.
When to Plant Foxglove in Mahnomen County, MN
July in the garden — Mahnomen County, Minnesota
If you only do a handful of things in the garden this July, make it these. They're sequenced around your zone's frost timing.
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Start foxglove indoors
These need a head start before your last frost (May 13). Sow into cells now so you're ready to transplant in a few weeks.
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Harvest foxglove as they ripen
This is the payoff month. Bring a basket, bring a friend, and get into the beds.
Looking ahead to August
- First harvests: foxglove
Foxglove (Digitalis purpurea) is a stately cottage garden classic, sending up dramatic 3–5 foot spires of tubular flowers — spotted purple, pink, white, or cream — in late spring and early summer. Technically biennial (flowering in its second year), foxglove perpetuates itself so freely from self-sown seed that established plantings appear to be permanent perennials. A key source plant for the heart medication digitalis, all parts are highly toxic if ingested. Bumblebees are the primary pollinators, crawling deep into each bell-shaped flower. Partial shade and cool, moist woodland-edge conditions suit foxglove best; it resents heat and drought.
Mahnomen County, Minnesota is in USDA Zone 4a. The average last spring frost is May 13 and the first fall frost is September 27, giving you a growing season of approximately 137 days.
At an elevation of 1,223 feet, Mahnomen County receives approximately 33.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Foxglove to ensure they mature before fall.
Mahnomen County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-7
Drainage
Well Drained
Foxglove Planting Risk Windows
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 Mahnomen County
How your county's soil matches Foxglove's growing requirements.
Soil pH
Your soil pH (5.9–7.0) overlaps with Foxglove's range (5.5–6.5), though not a perfect match.
Soil Texture
The silt loam soil in Mahnomen County is excellent for Foxglove — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Foxglove.
Organic Matter
Organic matter is excellent (4.0%) — Foxglove will thrive.
How to Plant Foxglove
Foxglove Water Budget
Monthly Watering Guide for Foxglove
Foxglove needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Foxglove Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.2" | 0" | ❄️ Dormant |
| Apr | — | 2.9" | 0" | ❄️ Dormant |
| May | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Jul | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Aug | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Sep | 4.3" | 3.1" | 1.2" | 💧 Light watering |
| Oct | — | 2.4" | 0" | ❄️ Dormant |
| Nov | — | 2.4" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Mahnomen County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Foxglove 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.
Foxglove Planting Timeline — Mahnomen County, MN
Foxglove Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 4 | Mar 4 – Mar 18 |
| Transplant Outdoors | May 27 | May 27 – Jun 10 |
| Direct Sow | May 27 | May 27 – Jun 17 |
| Bloom | July 22 | Jul 22 – Sep 2 |
Plant 0.1" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
80–120 days
🧪 Soil pH
Needs 5.5–6.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 4a
📆 Growing Season
137 days in Mahnomen County
Growing Tips for Foxglove in Mahnomen County
Direct sow Foxglove outdoors after May 13 in Mahnomen County when soil has warmed and frost danger has passed.
General growing tips
Sow seeds indoors 8–10 weeks before last frost or direct-sow outdoors in late spring/early summer for next-year bloom (biennial cycle). Surface-sow — seeds need light to germinate. Transplant after last frost into cool, moist, well-amended soil. Morning sun with afternoon shade is ideal; full shade reduces bloom but is tolerated. Keep consistently moist. First-year plants form a basal rosette only; second-year plants produce flower spikes. After bloom, cut the main spike before seed scatters to prevent excessive spreading, or leave some spikes to self-seed for naturalizing. Perennial species (D. grandiflora, D. x mertonensis) maintain clumps without requiring self-seeding. Wear gloves when handling — all plant parts toxic.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Foxglove in Other Locations
Frequently Asked Questions
When should I plant Foxglove in Mahnomen County, MN?
Mahnomen County is in Zone 4a with an average last frost of May 13. Plan your Foxglove planting based on this frost date — see the calendar above for exact timing.
What planting zone is Mahnomen County, MN?
Mahnomen County, Minnesota is in USDA Hardiness Zone 4a. The average last spring frost is May 13 and first fall frost is September 27.
When should I plant Foxglove in Mahnomen County, MN?
In Mahnomen County, MN, plant Foxglove after the last frost (around May 13) and before the first frost (around September 27). Best results when soil holds above 50°F.
What growing zone is Mahnomen County, MN for Foxglove?
Mahnomen County sits in USDA Zone 4a. Foxglove grows reliably in zones 3a through 9a, so it's a good fit here.
Can Foxglove grow in Mahnomen County's climate?
Yes — Foxglove grows well in Mahnomen County's temperate climate. Mahnomen County averages a 137-day frost-free season, with last frost around May 13 and first frost around September 27.
Your Mahnomen County Garden Planner — Free
A 22-page printable planner built for Mahnomen County (Zone 4a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.