When to Plant Geraniums in Armstrong County, PA
Armstrong County, Pennsylvania gardeners: here's your June plan
Your garden in Armstrong County, Pennsylvania is working on a schedule, even when you're not. Here's where you should be this June.
To set up a strong July, finish these tasks
- Starting indoors: geraniums
- First harvests: geraniums
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.
Armstrong County, Pennsylvania is in USDA Zone 6b. The average last spring frost is April 29 and the first fall frost is October 18, giving you a growing season of approximately 172 days.
At an elevation of 213 feet, Armstrong County receives approximately 49.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Geraniums during the growing season.
Armstrong County Soil Profile
Soil Type
Silt Loam
Soil pH
5-6.3
Drainage
Well Drained
Geraniums 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 Armstrong County
How your county's soil matches Geraniums's growing requirements.
Soil pH
Your soil pH (5.0–6.3) is more acidic than Geraniums prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Armstrong County is excellent for Geraniums — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.8%). Annual compost additions will help Geraniums.
How to Plant Geraniums
Succession Planting Geraniums
Sow every 8 weeks. Last sowing by Jul 10 to harvest before frost.
Geraniums Water Budget
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 | — | 3.6" | 0" | ❄️ Dormant |
| Feb | — | 3.6" | 0" | ❄️ Dormant |
| Mar | — | 4.3" | 0" | ❄️ Dormant |
| Apr | 4.3" | 4.7" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 5" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 4.7" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Sep | 4.3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Nov | — | 3.8" | 0" | ❄️ Dormant |
| Dec | — | 3.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Armstrong County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Geraniums 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.
Geraniums Planting Timeline — Armstrong County, PA
Geraniums Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 18 | Feb 18 – Mar 4 |
| Transplant Outdoors | May 6 | May 6 – May 20 |
| Bloom | July 15 | Jul 15 – Oct 21 |
Plant 0.1" deep · 12" apart · Rows 14" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Natural rainfall sufficient
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 6b
📆 Growing Season
172 days in Armstrong County
Growing Tips for Geraniums in Armstrong County
Direct sow Geraniums outdoors after April 29 in Armstrong County when soil has warmed and frost danger has passed.
General growing tips
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 Armstrong County, PA?
Armstrong County is in Zone 6b with an average last frost of April 29. Plan your Geraniums planting based on this frost date — see the calendar above for exact timing.
What planting zone is Armstrong County, PA?
Armstrong County, Pennsylvania is in USDA Hardiness Zone 6b. The average last spring frost is April 29 and first fall frost is October 18.
Your Armstrong County Garden Planner — Free
A 22-page printable planner built for Armstrong 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.