Blog

When to Plant Foxglove in Union County, OR

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.

Union County, Oregon is in USDA Zone 6b. The average last spring frost is May 12 and the first fall frost is September 26, giving you a growing season of approximately 137 days.

At an elevation of 2,751 feet, Union County receives approximately 23.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Foxglove during the growing season.

Perennial Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting
Union County, OR (Zone 6b) Short season
137 days
Last Spring Frost May 12
137 growing days
First Fall Frost September 26

Union County Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.6

Drainage

Well Drained

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 2.9" 0" ❄️ Dormant
Feb 2.6" 0" ❄️ Dormant
Mar 2.3" 0" ❄️ Dormant
Apr 1.5" 0" ❄️ Dormant
May 4.3" 1.5" 2.8" 🚿 Regular watering
Jun 4.3" 0.9" 3.4" 🚿 Regular watering
Jul 4.3" 0.4" 3.9" 🚿 Regular watering
Aug 4.3" 0.5" 3.8" 🚿 Regular watering
Sep 4.3" 1" 3.3" 🚿 Regular watering
Oct 2" 0" ❄️ Dormant
Nov 3.8" 0" ❄️ Dormant
Dec 4.2" 0" ❄️ Dormant

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

Foxglove Planting Timeline — Union County, OR

Foxglove Planting Calendar

Activity When Date Range
Start Indoors March 10 Mar 10 – Mar 24
Transplant Outdoors May 19 May 19 – Jun 2
Direct Sow May 19 May 19 – Jun 9
Bloom July 14 Jul 14 – Aug 18

Plant 0.1" deep · 18" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

80–120 days

🧪 Soil pH

Needs 5.5–6.5 · Your soil: N/A

🗺️ USDA Zone

Zone 6b

📆 Growing Season

137 days in Union County

Growing Tips for Union County

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 →

Frequently Asked Questions

When should I plant Foxglove in Union County, OR?

Union County is in Zone 6b with an average last frost of May 12. Plan your Foxglove planting based on this frost date — see the calendar above for exact timing.

What planting zone is Union County, OR?

Union County, Oregon is in USDA Hardiness Zone 6b. The average last spring frost is May 12 and first fall frost is September 26.

🌱

Your Union County Garden Planner — Free

A 22-page printable planner built for Union County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Union County, OR. 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.