When to Plant Potatoes in Franklin County, ME
May to-do list for Franklin County, Maine
May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Franklin County, Maine.
-
Harden off and plant potatoes
Pinch off the lowest leaves on each seedling before you plant — it reduces water loss while the roots catch up.
-
Outdoor sowing time: potatoes
Your soil is 56°F — warm enough for these to germinate without babying.
Potatoes are a versatile staple crop that produces tubers underground. They come in hundreds of varieties with varying colors, textures, and maturity dates.
Franklin County, Maine is in USDA Zone 5a. The average last spring frost is May 14 and the first fall frost is September 28, giving you a growing season of approximately 137 days.
At an elevation of 244 feet, Franklin County receives approximately 40.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Potatoes to ensure they mature before fall.
Franklin County Soil Profile
Soil Type
Silt Loam
Soil pH
5.2-6.6
Drainage
Well Drained
Plant 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 Franklin County
How your county's soil matches Potatoes's growing requirements.
Soil pH
Your soil pH (5.2–6.6) overlaps with Potatoes's range (5.0–6.5), though not a perfect match.
Soil Texture
The silt loam soil in Franklin County is excellent for Potatoes — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.2%). Annual compost additions will help Potatoes.
How to Plant Potatoes
Succession Planting Potatoes
Sow every 8 weeks. Last sowing by May 31 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Potatoes
Potatoes needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Potatoes Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3.2" | 0" | ❄️ Dormant |
| Feb | — | 2.6" | 0" | ❄️ Dormant |
| Mar | — | 3.9" | 0" | ❄️ Dormant |
| Apr | — | 3.1" | 0" | ❄️ Dormant |
| May | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Jun | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Jul | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Aug | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Sep | 4.3" | 3" | 1.3" | 💧 Light watering |
| Oct | — | 3.4" | 0" | ❄️ Dormant |
| Nov | — | 2.7" | 0" | ❄️ Dormant |
| Dec | — | 3.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Franklin County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Potatoes 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.
Potatoes Planting Timeline — Franklin County, ME
Potatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 19 | Mar 19 – Apr 2 |
| Transplant Outdoors | May 28 | May 28 – Jun 11 |
| Direct Sow | May 21 | May 21 – Jun 11 |
| Harvest | August 6 | Aug 6 – Oct 15 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | — |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Natural rainfall sufficient
📅 Days to Maturity
70–120 days
🧪 Soil pH
Needs 5–6.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 5a
📆 Growing Season
137 days in Franklin County
Growing Tips for Potatoes in Franklin County
Direct sow Potatoes outdoors after May 14 in Franklin County when soil has warmed and frost danger has passed.
Common pests for Potatoes in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.
General growing tips
Plant seed potatoes (not grocery store potatoes) 4 inches deep in spring. Hill soil around stems as plants grow to prevent greening. Stop watering when plants die back.
Recommended Potatoes Varieties for Franklin County
Early-maturing potatoes for your season
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Potatoes in Other Locations
Frequently Asked Questions
When should I plant Potatoes in Franklin County, ME?
Franklin County is in Zone 5a with an average last frost of May 14. Plan your Potatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is Franklin County, ME?
Franklin County, Maine is in USDA Hardiness Zone 5a. The average last spring frost is May 14 and first fall frost is September 28.
Your Franklin County Garden Planner — Free
A 24-page printable planner built for Franklin 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.