When to Plant Foxglove in Travis County, TX
Your July game plan for Travis County, Texas
Welcome to July in Zone 9a. These are the moves that will have the biggest impact on your growing season.
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.
Travis County, Texas is in USDA Zone 9a. The average last spring frost is March 6 and the first fall frost is November 23, giving you a growing season of approximately 262 days.
At an elevation of 3,682 feet, Travis County receives approximately 66.3 inches of rainfall annually with predominantly clay soil. Summer highs average 92°F, providing good warmth for Foxglove during the growing season. Clay soil retains moisture well for Foxglove, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Foxglove root diseases.
Travis County Soil Profile
Soil Type
Clay
Soil pH
6.8-8.4
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 Travis County
How your county's soil matches Foxglove's growing requirements.
Soil pH
Your soil pH (6.8–8.4) is more alkaline than Foxglove prefers (5.5–6.5). Add sulfur or peat moss to lower pH.
Soil Texture
Your clay soil in Travis County is workable for Foxglove. Add compost annually to improve structure.
Organic Matter
Organic matter is moderate (3.0%). Annual compost additions will help Foxglove.
How to Plant Foxglove
Succession Planting Foxglove
Sow every 9.1 weeks. Last sowing by Jul 26 to harvest before frost.
Foxglove Water Budget
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 | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 2" | 0" | ❄️ Dormant |
| Mar | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Apr | 4.3" | 6.6" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 11.1" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 9.5" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 8.6" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 8.2" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 5.9" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Nov | 4.3" | 2.5" | 1.8" | 💧 Light watering |
| Dec | — | 1.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Travis 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 — Travis County, TX
Foxglove Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 9 | Jan 9 – Jan 23 |
| Transplant Outdoors | February 20 | Feb 20 – Mar 6 |
| Direct Sow | February 20 | Feb 20 – Mar 13 |
| Bloom | April 10 | Apr 10 – May 1 |
Plant 0.1" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Transplant Outdoors Direct Sow |
| March | Transplant Outdoors Direct Sow |
| April | Bloom |
| May | Bloom |
| June | — |
| July | — |
| 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 9a
📆 Growing Season
262 days in Travis County
Growing Tips for Foxglove in Travis County
Direct sow Foxglove outdoors after March 06 in Travis County when soil has warmed and frost danger has passed.
With Travis County's clay soil (37% clay), work in 3-4 inches of compost before planting Foxglove. Avoid tilling when soil is wet to prevent compaction.
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 Travis County, TX?
Travis County is in Zone 9a with an average last frost of March 6. Plan your Foxglove planting based on this frost date — see the calendar above for exact timing.
What planting zone is Travis County, TX?
Travis County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is March 6 and first fall frost is November 23.
Your Travis County Garden Planner — Free
A 22-page printable planner built for Travis County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.