When to Plant Geraniums in Gillespie County, TX
Geraniums (Pelargonium × hortorum) are tender perennials grown as warm-season annuals throughout North America. Prized for their bold flower clusters, long bloom period, and tolerance of summer heat when planted in well-drained soil, they anchor window boxes, containers, and bed borders from late spring until hard frost. Zones 9b–11b can overwinter plants in the ground.
Gillespie County, Texas is in USDA Zone 8b. The average last spring frost is March 19 and the first fall frost is November 14, giving you a growing season of approximately 240 days.
At an elevation of 3,036 feet, Gillespie County receives approximately 65.8 inches of rainfall annually with predominantly loam soil. Summer highs average 91°F, providing good warmth for Geraniums during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Geraniums root diseases.
Gillespie County Soil Profile
Soil Type
Loam
Soil pH
6.5-7.8
Drainage
Well Drained
Monthly Watering Guide for Geraniums
Geraniums needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Geraniums Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 2.3" | 0" | ❄️ Dormant |
| Mar | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Apr | 4.3" | 6.6" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 9.4" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 12" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 9.3" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 6.9" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 5.2" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Nov | 4.3" | 2.5" | 1.8" | 💧 Light watering |
| Dec | — | 1.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Gillespie County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Geraniums Planting Timeline — Gillespie County, TX
Geraniums Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 8 | Jan 8 – Jan 22 |
| Transplant Outdoors | March 5 | Mar 5 – Mar 19 |
| Bloom | May 14 | May 14 – Oct 15 |
Plant 0.1" deep · 12" apart · Rows 14" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | — |
| March | Transplant Outdoors |
| April | — |
| May | Bloom |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 8b
📆 Growing Season
240 days in Gillespie County
Growing Tips for Gillespie County
Start seeds indoors 10–12 weeks before last frost — germination is slow and erratic without bottom heat (70–75°F). Transplant after frost danger passes. Geraniums rarely direct-sown; cuttings or transplants are the standard. Deadhead spent umbels weekly to maintain continuous bloom. Let soil dry slightly between waterings to prevent root rot. In zones 10–11 plants may be left in ground year-round or overwintered as houseplants.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Geraniums in Other Locations
Frequently Asked Questions
When should I plant Geraniums in Gillespie County, TX?
Gillespie County is in Zone 8b with an average last frost of March 19. Plan your Geraniums planting based on this frost date — see the calendar above for exact timing.
What planting zone is Gillespie County, TX?
Gillespie County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 19 and first fall frost is November 14.
Your Gillespie County Garden Planner — Free
A 22-page printable planner built for Gillespie County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.