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When to Plant Foxglove in Roberts County, TX

Roberts County, Texas Zone 7a June

June to-do list for Roberts County, Texas

If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.

Avg. last frost April 17
Avg. first frost October 24
Soil temp (4") 76°F
Watering High
Pest pressure High
Daylight 14.4 hrs
  1. Start foxglove indoors

    A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.

  2. Basket week: foxglove

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

July will be here before you know it — start on
  • First harvests: foxglove

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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.

Roberts County, Texas is in USDA Zone 7a. The average last spring frost is April 17 and the first fall frost is October 24, giving you a growing season of approximately 190 days.

At an elevation of 1,068 feet, Roberts County receives approximately 51 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 98°F, so Foxglove may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Foxglove will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Foxglove root diseases.

Perennial Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting
Roberts County, TX (Zone 7a) Moderate season
190 days
Last Spring Frost April 17
190 growing days
First Fall Frost October 24

Roberts County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.5-8.8

Drainage

Well Drained

Foxglove Planting Risk Windows

Early Start (70% safe) ✓ Fits season (98 days to spare)
Start indoors: Feb 14 Transplant: Apr 18 🌸 Bloom: Jun 6 – Jul 11
Recommended (50%) ✓ Fits season (99 days to spare)
Start indoors: Feb 20 Transplant: Apr 24 🌸 Bloom: Jun 12 – Jul 17
Safe Start (90%) ✓ Fits season (96 days to spare)
Start indoors: Mar 7 Transplant: May 9 🌸 Bloom: Jun 27 – Aug 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 Roberts County

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

Soil pH

Your soil pH (7.5–8.8) is more alkaline than Foxglove prefers (5.5–6.5). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Roberts County warms quickly in spring but drains fast. Foxglove will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is low (0.9%). Add 2-3 inches of compost before planting Foxglove.

How to Plant Foxglove

0.1"
Planting Depth
18"
Between Plants
24"
Between Rows

Succession Planting Foxglove

2
successive plantings in your 190-day season

Sow every 9.1 weeks. Last sowing by Jun 26 to harvest before frost.

Foxglove Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 3.5" 0" ❄️ Dormant
Feb 3.3" 0" ❄️ Dormant
Mar 2.9" 0" ❄️ Dormant
Apr 4.3" 1.9" 2.4" 🚿 Regular watering
May 4.3" 1.1" 3.2" 🚿 Regular watering
Jun 4.3" 1.5" 2.8" 🚿 Regular watering
Jul 4.3" 9.3" 0" ✅ Rainfall sufficient
Aug 4.3" 9.5" 0" ✅ Rainfall sufficient
Sep 4.3" 6.3" 0" ✅ Rainfall sufficient
Oct 4.3" 5" 0" ✅ Rainfall sufficient
Nov 3.3" 0" ❄️ Dormant
Dec 3.3" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Roberts 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 needs ~2,350 GDD — county provides 4,465 GDD Excellent fit

Foxglove Planting Timeline — Roberts County, TX

Foxglove Planting Calendar

Activity When Date Range
Start Indoors February 20 Feb 20 – Mar 6
Transplant Outdoors April 24 Apr 24 – May 8
Direct Sow April 24 Apr 24 – May 15
Bloom June 12 Jun 12 – Jul 17

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

80–120 days

🧪 Soil pH

Needs 5.5–6.5 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 7a

📆 Growing Season

190 days in Roberts County

Growing Tips for Foxglove in Roberts County

Direct sow Foxglove outdoors after April 17 in Roberts County when soil has warmed and frost danger has passed.

Sandy soil in Roberts County dries quickly — mulch Foxglove with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 98°F in Roberts County, provide afternoon shade for Foxglove and water deeply in the morning.

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 →

Frequently Asked Questions

When should I plant Foxglove in Roberts County, TX?

Roberts County is in Zone 7a with an average last frost of April 17. Plan your Foxglove planting based on this frost date — see the calendar above for exact timing.

What planting zone is Roberts County, TX?

Roberts County, Texas is in USDA Hardiness Zone 7a. The average last spring frost is April 17 and first fall frost is October 24.

🌱

Your Roberts County Garden Planner — Free

A 22-page printable planner built for Roberts 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 Roberts County, TX. 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.