When to plant Hydrangeas in Union County County,
In Union County County, Hydrangeas is a spring-only crop. Plant April 11–April 25 once soil hits 50°F.
When to Plant Hydrangeas in Union County, GA
Hydrangeas (Hydrangea spp.) are among the most spectacular summer-blooming shrubs, with large mophead, lacecap, or panicle flower clusters lasting weeks in the garden and drying beautifully for arrangements. Native to Asia and North America alike, the genus spans several garden species with different hardiness and blooming habits. Panicle hydrangeas (H. paniculata, e.g., Limelight) are the most cold-hardy (Zone 3) and most reliable bloomers; smooth hydrangeas (H. arborescens, e.g., Annabelle) are equally tough. Bigleaf hydrangeas (H. macrophylla) are prized for blue/pink color-shifting blooms but require reliable snow cover or winter protection in Zones 5–6. Flower color in macrophylla types is determined by soil pH (acidic = blue, alkaline = pink).
Union County, Georgia is in USDA Zone 7b. The average last spring frost is April 11 and the first fall frost is October 23, giving you a growing season of approximately 195 days.
At an elevation of 175 feet, Union County receives approximately 61.4 inches of rainfall annually with predominantly clay loam soil. Summer highs average 93°F, providing good warmth for Hydrangeas during the growing season. Clay soil retains moisture well for Hydrangeas, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Hydrangeas root diseases.
Union County Soil Profile
Soil Type
Clay Loam
Soil pH
5.8-6.2
Drainage
Well Drained
Monthly Watering Guide for Hydrangeas
Hydrangeas needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Hydrangeas Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 6" | 0" | ❄️ Dormant |
| Feb | — | 4.6" | 0" | ❄️ Dormant |
| Mar | — | 5.8" | 0" | ❄️ Dormant |
| Apr | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 5.3" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 5.1" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 5.7" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 6.2" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Nov | — | 4.2" | 0" | ❄️ Dormant |
| Dec | — | 5.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Union County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Hydrangeas Planting Timeline — Union County, GA
Hydrangeas Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 31 | Jan 31 – Feb 14 |
| Transplant Outdoors | April 11 | Apr 11 – Apr 25 |
| Bloom | June 20 | Jun 20 – Oct 17 |
Plant 1" deep · 48" apart · Rows 60" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Start Indoors |
| March | — |
| April | Transplant Outdoors |
| May | — |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
90–150 days
🧪 Soil pH
Needs 5.5–6.5 · Your soil: N/A
🗺️ USDA Zone
Zone 7b
📆 Growing Season
195 days in Union County
Growing Tips for Union County
Plant container-grown specimens in spring or fall, spacing at least 3–5 feet apart to allow for mature shrub spread. Most hydrangeas prefer morning sun with afternoon shade, especially in Zones 7+. Keep consistently moist — the name derives from the Greek for water vessel. Prune panicle and smooth types in late winter/early spring (they bloom on new wood). Prune bigleaf types only lightly after bloom; cutting stems in fall removes next year's buds. In Zone 5–6, protect bigleaf varieties with burlap or wire cages filled with leaves over winter. Fall planting (Zones 5+) gives excellent root establishment before summer heat. Year 2+ plants reach full size and bloom.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Hydrangeas in Other Locations
Frequently Asked Questions
When should I plant Hydrangeas in Union County, GA?
Union County is in Zone 7b with an average last frost of April 11. Plan your Hydrangeas planting based on this frost date — see the calendar above for exact timing.
What planting zone is Union County, GA?
Union County, Georgia is in USDA Hardiness Zone 7b. The average last spring frost is April 11 and first fall frost is October 23.
When should I plant Hydrangeas in Union County County, ?
In Union County County, , plant Hydrangeas after the last frost (around April 11) and before the first frost (around October 23). Best results when soil holds above 50°F.
What growing zone is Union County County, for Hydrangeas?
Union County County sits in USDA Zone 7b. Hydrangeas grows reliably in zones 3a through 9a, so it's a good fit here.
Can Hydrangeas grow in Union County County's climate?
Yes — Hydrangeas grows well in Union County County's temperate climate. Union County County averages a 195-day frost-free season, with last frost around April 11 and first frost around October 23.
Your Union County Garden Planner — Free
A 22-page printable planner built for Union County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.