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When to Plant Potatoes in Mineral County, CO

Potatoes are a versatile staple crop that produces tubers underground. They come in hundreds of varieties with varying colors, textures, and maturity dates.

Mineral County, Colorado is in USDA Zone 4a. The average last spring frost is June 10 and the first fall frost is September 13, giving you a growing season of approximately 95 days.

At an elevation of 7,809 feet, Mineral County receives approximately 12.8 inches of rainfall annually with predominantly loam soil. Summer highs average 80ยฐF, so choose short-season varieties of Potatoes to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Potatoes successfully. Mulch heavily to conserve soil moisture.

Mineral County, CO (Zone 4a) Very short season
95 days
Last Spring Frost June 10
95 growing days
First Fall Frost September 13

Mineral County Soil Profile

Soil Type

Loam

Soil pH

6.8-8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Mar 27 Transplant: Jun 19 🍅 Harvest: Aug 28 – Nov 6
Recommended (50%) ✗ May not fit
Start indoors: Apr 8 Transplant: Jul 1 🍅 Harvest: Sep 9 – Nov 18
Safe Start (90%) ✗ May not fit
Start indoors: Apr 24 Transplant: Jul 17 🍅 Harvest: Sep 25 – Dec 4

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 Mineral County

How your county's soil matches Potatoes's growing requirements.

Soil pH

Your soil pH (6.8โ€“8.0) is more alkaline than Potatoes prefers (5.0โ€“6.5). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Mineral County is excellent for Potatoes โ€” good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Potatoes.

Organic Matter

Organic matter is moderate (2.2%). Annual compost additions will help Potatoes.

How to Plant Potatoes

1"
Planting Depth
15"
Between Plants
24"
Between Rows

How Much Potatoes to Grow

3-5 lbs
Average yield per plant
5
Plants per person
12.5 sq ft
Space per person

For a family of 4, plant approximately 20 potatoes plants in about 50 sq ft. In Mineral County's 95-day season, you'll have plenty of time for a full harvest. Plan your garden layout →

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.6″/week
You supply
0.9″/week
Watering frequency 2-3 times/week
Season total 745 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” 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 โ€” 1" 0" โ„๏ธ Dormant
Feb โ€” 0.8" 0" โ„๏ธ Dormant
Mar โ€” 1.2" 0" โ„๏ธ Dormant
Apr โ€” 1.1" 0" โ„๏ธ Dormant
May โ€” 1.6" 0" โ„๏ธ Dormant
Jun 4.3" 0.8" 3.5" ๐Ÿšฟ Regular watering
Jul 4.3" 1" 3.3" ๐Ÿšฟ Regular watering
Aug 4.3" 1.4" 2.9" ๐Ÿšฟ Regular watering
Sep 4.3" 0.9" 3.4" ๐Ÿšฟ Regular watering
Oct โ€” 1.2" 0" โ„๏ธ Dormant
Nov โ€” 0.9" 0" โ„๏ธ Dormant
Dec โ€” 0.8" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Junโ€“Sep in Mineral County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 needs ~950 GDD — county provides 950 GDD Tight fit

Potatoes Planting Timeline โ€” Mineral County, CO

Potatoes Planting Calendar

Activity When Date Range
Start Indoors April 8 Apr 8 โ€“ Apr 22
Transplant Outdoors July 1 Jul 1 โ€“ Jul 15
Direct Sow June 24 Jun 24 โ€“ Jul 15
Harvest September 9 Sep 9 โ€“ Nov 18

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Start Indoors
May โ€”
June Direct Sow
July Transplant Outdoors Direct Sow
August โ€”
September Harvest
October Harvest
November Harvest
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 2-3 times/week

๐Ÿ“… Days to Maturity

70โ€“120 days

๐Ÿงช Soil pH

Needs 5โ€“6.5 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 4a

๐Ÿ“† Growing Season

95 days in Mineral County

Growing Tips for Potatoes in Mineral County

Direct sow Potatoes outdoors after June 10 in Mineral County when soil has warmed and frost danger has passed.

Your 95.0-day growing season in Mineral 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.

Mineral County receives only 13" of rain annually. Potatoes needs consistent moisture โ€” 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 Mineral County

Early-maturing potatoes for your season

Yukon Gold (65d) Red Norland (70d) Irish Cobbler (70d)

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Cucumber
  • Squash Summer

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Potatoes in Mineral County, CO?

Mineral County is in Zone 4a with an average last frost of June 10. Plan your Potatoes planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Mineral County, CO?

Mineral County, Colorado is in USDA Hardiness Zone 4a. The average last spring frost is June 10 and first fall frost is September 13.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Mineral County gardeners in Zone 4a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Mineral County, CO. Local conditions may vary. Last updated: April 2026.