When to plant Potatoes in Custer County County,
Custer County County's 79-day season only supports one Potatoes planting per year. Sow between June 25 and July 16 for the best chance at full maturity before September 5.
When to Plant Potatoes in Custer County, ID
June in Custer County, Idaho — your action list
If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.
-
Direct-sow potatoes
Succession planting is the secret here. Put in a row now, another in 2 weeks, a third in 4.
A few tasks this June that'll pay off in July
- Transplants going out: potatoes
Potatoes are a versatile staple crop that produces tubers underground. They come in hundreds of varieties with varying colors, textures, and maturity dates.
Custer County, Idaho is in USDA Zone 5b. The average last spring frost is June 18 and the first fall frost is September 5, giving you a growing season of approximately 79 days.
At an elevation of 5,189 feet, Custer County receives approximately 20.6 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Potatoes to ensure they mature before fall.
Custer County Soil Profile
Soil Type
Loam
Soil pH
6.3-8
Drainage
Well Drained
Potatoes 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 Custer County
How your county's soil matches Potatoes's growing requirements.
Soil pH
Your soil pH (6.3–8.0) is more alkaline than Potatoes prefers (5.0–6.5). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Custer County is excellent for Potatoes — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.3%). Annual compost additions will help Potatoes.
How to Plant Potatoes
How Much Potatoes to Grow
For a family of 4, plant approximately 20 potatoes plants in about 50 sq ft. In Custer County's 79-day season, you'll have plenty of time for a full harvest. Plan your garden layout →
Potatoes Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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 | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 1.3" | 0" | ❄️ Dormant |
| Mar | — | 1.7" | 0" | ❄️ Dormant |
| Apr | — | 2.4" | 0" | ❄️ Dormant |
| May | — | 2.3" | 0" | ❄️ Dormant |
| Jun | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Jul | 4.3" | 2" | 2.3" | 🚿 Regular watering |
| Aug | 4.3" | 2.1" | 2.2" | 🚿 Regular watering |
| Sep | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Oct | — | 1.6" | 0" | ❄️ Dormant |
| Nov | — | 1.4" | 0" | ❄️ Dormant |
| Dec | — | 1.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Sep in Custer 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 — Custer County, ID
Potatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 23 | Apr 23 – May 7 |
| Transplant Outdoors | July 2 | Jul 2 – Jul 16 |
| Direct Sow | June 25 | Jun 25 – Jul 16 |
| Harvest | September 10 | Sep 10 – Nov 19 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Start Indoors |
| June | Direct Sow |
| July | Transplant Outdoors Direct Sow |
| August | — |
| September | Harvest |
| October | Harvest |
| November | Harvest |
| 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: too_alkaline
🗺️ USDA Zone
Zone 5b
📆 Growing Season
79 days in Custer County
Growing Tips for Potatoes in Custer County
Direct sow Potatoes outdoors after June 18 in Custer County when soil has warmed and frost danger has passed.
Your 79.0-day growing season in Custer County is tight for Potatoes (70.0-120.0 days to maturity). Start indoors and choose early-maturing varieties.
Common pests for Potatoes in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.
Custer County receives only 21" of rain annually. Potatoes needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
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 Custer 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 Custer County, ID?
Custer County is in Zone 5b with an average last frost of June 18. Plan your Potatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is Custer County, ID?
Custer County, Idaho is in USDA Hardiness Zone 5b. The average last spring frost is June 18 and first fall frost is September 5.
When should I plant Potatoes in Custer County, ?
In Custer County, , plant Potatoes after the last frost (around June 18) and before the first frost (around September 5). Best results when soil holds above 50°F.
What growing zone is Custer County, for Potatoes?
Custer County sits in USDA Zone 5b. Potatoes grows reliably in zones 3a through 10b, so it's a good fit here.
Can Potatoes grow in Custer County's climate?
Yes — Potatoes grows well in Custer County's temperate climate. Custer County averages a 79-day frost-free season, with last frost around June 18 and first frost around September 5.
Your Custer County Garden Planner — Free
A 22-page printable planner built for Custer County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.