When to plant Geraniums in Penobscot County, ME
In Penobscot County, Geraniums is a spring-only crop. Plant May 17–May 31 once soil hits 50°F.
When to Plant Geraniums in Penobscot County, ME
July to-do list for Penobscot County, Maine
July rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Penobscot County, Maine.
-
Get geraniums seeds going inside
Label every cell. You will absolutely forget which is which otherwise.
-
Pick geraniums
The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.
Before August arrives, get these ready
- 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.
Penobscot County, Maine is in USDA Zone 5a. The average last spring frost is May 10 and the first fall frost is October 2, giving you a growing season of approximately 145 days.
At an elevation of 842 feet, Penobscot County receives approximately 38.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Geraniums to ensure they mature before fall.
Penobscot County Soil Profile
Soil Type
Silt Loam
Soil pH
4.8-6.7
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 Penobscot County
How your county's soil matches Geraniums's growing requirements.
Soil pH
Your soil pH (4.8–6.7) is more acidic than Geraniums prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Penobscot County is excellent for Geraniums — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.6%). Annual compost additions will help Geraniums.
How to Plant Geraniums
Succession Planting Geraniums
Sow every 8 weeks. Last sowing by Jun 24 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 | — | 2.4" | 0" | ❄️ Dormant |
| Feb | — | 2.3" | 0" | ❄️ Dormant |
| Mar | — | 3" | 0" | ❄️ Dormant |
| Apr | — | 3.4" | 0" | ❄️ Dormant |
| May | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Jun | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Jul | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Aug | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| Sep | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Oct | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Nov | — | 3.2" | 0" | ❄️ Dormant |
| Dec | — | 2.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Penobscot 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 — Penobscot County, ME
Geraniums Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 1 | Mar 1 – Mar 15 |
| Transplant Outdoors | May 17 | May 17 – May 31 |
| Bloom | July 26 | Jul 26 – Oct 18 |
Plant 0.1" deep · 12" apart · Rows 14" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| 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 5a
📆 Growing Season
145 days in Penobscot County
Growing Tips for Geraniums in Penobscot County
Direct sow Geraniums outdoors after May 10 in Penobscot 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 Penobscot County, ME?
Penobscot County is in Zone 5a with an average last frost of May 10. Plan your Geraniums planting based on this frost date — see the calendar above for exact timing.
What planting zone is Penobscot County, ME?
Penobscot County, Maine is in USDA Hardiness Zone 5a. The average last spring frost is May 10 and first fall frost is October 2.
When should I plant Geraniums in Penobscot County, ME?
In Penobscot County, ME, plant Geraniums after the last frost (around May 10) and before the first frost (around October 2). Best results when soil holds above 50°F.
What growing zone is Penobscot County, ME for Geraniums?
Penobscot County sits in USDA Zone 5a. Geraniums grows reliably in zones 2a through 11b, so it's a good fit here.
Can Geraniums grow in Penobscot County's climate?
Yes — Geraniums grows well in Penobscot County's temperate climate. Penobscot County averages a 145-day frost-free season, with last frost around May 10 and first frost around October 2.
Your Penobscot County Garden Planner — Free
A 22-page printable planner built for Penobscot County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.