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When to Plant Pumpkin in Mineral County, CO

Mineral County, Colorado Zone 5a May

May in Mineral County, Colorado — your action list

We've pulled the most time-sensitive tasks for Mineral County, Colorado this May and put them front and centre. Tackle them in order.

Avg. last frost June 10
Avg. first frost September 13
Soil temp (4") 34°F
Watering High
Pest pressure Low
Daylight 14 hrs
June will be here before you know it — start on
  • Transplants going out: pumpkin
  • Direct-sowing: pumpkin

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Pumpkins are large-fruited squash varieties grown for eating, decoration, and seed production. They require ample space and a long, warm growing season.

Mineral County, Colorado is in USDA Zone 5a. 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 80°F, so choose short-season varieties of Pumpkin to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Pumpkin successfully. Mulch heavily to conserve soil moisture.

Mineral County, CO (Zone 5a) 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: Apr 24 Transplant: Jun 12 🍅 Harvest: Sep 11 – Oct 30
Recommended (50%) ✗ May not fit
Start indoors: May 6 Transplant: Jun 24 🍅 Harvest: Sep 23 – Nov 11
Safe Start (90%) ✗ May not fit
Start indoors: May 22 Transplant: Jul 10 🍅 Harvest: Oct 9 – Nov 27

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 Pumpkin's growing requirements.

Soil pH

Your soil pH (6.8–8.0) overlaps with Pumpkin's range (6.0–7.5), though not a perfect match.

Soil Texture

The loam soil in Mineral County is excellent for Pumpkin — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Pumpkin.

Organic Matter

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

How to Plant Pumpkin

1"
Planting Depth
30"
Between Plants
42"
Between Rows

Plant Water Budget

Plant needs
1.3″/week
Rainfall provides
0.6″/week
You supply
1.4″/week
Watering frequency 2-3 times/week
Season total 1,141 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Pumpkin

Pumpkin needs approximately 1.3 inches of water per week (5.6" per month). Here's how your county's rainfall compares month by month.

Month Pumpkin Needs Rainfall You Supplement Action
Jan 1" 0" ❄️ Dormant
Feb 0.8" 0" ❄️ Dormant
Mar 1.2" 0" ❄️ Dormant
Apr 1.1" 0" ❄️ Dormant
May 1.6" 0" ❄️ Dormant
Jun 5.6" 0.8" 4.8" 🚿 Regular watering
Jul 5.6" 1" 4.6" 🚿 Regular watering
Aug 5.6" 1.4" 4.2" 🚿 Regular watering
Sep 5.6" 0.9" 4.7" 🚿 Regular watering
Oct 1.2" 0" ❄️ Dormant
Nov 0.9" 0" ❄️ Dormant
Dec 0.8" 0" ❄️ Dormant

Water needs are for active growing months only (Jun–Sep in Mineral County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Pumpkin 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.

Pumpkin needs ~1,025 GDD — county provides 950 GDD Tight fit

Pumpkin Planting Timeline — Mineral County, CO

Pumpkin Planting Calendar

Activity When Date Range
Start Indoors May 6 May 6 – May 20
Transplant Outdoors June 24 Jun 24 – Jul 8
Direct Sow June 17 Jun 17 – Jul 8
Harvest September 23 Sep 23 – Nov 11

Plant 1" deep · 30" apart · Rows 42" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.3"/week · 2-3 times/week

📅 Days to Maturity

85–120 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 5a

📆 Growing Season

95 days in Mineral County

Growing Tips for Pumpkin in Mineral County

Direct sow Pumpkin 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 Pumpkin (85.0-120.0 days to maturity). Start indoors and choose early-maturing varieties.

Common pests for Pumpkin in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.

Mineral County receives only 13" of rain annually. Pumpkin needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Direct sow on mounds after last frost. Allow 6-10 feet between plants. Slip a board under developing fruit to prevent rot. Harvest when rind is hard and deep in color.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Pumpkin in Mineral County, CO?

Mineral County is in Zone 5a with an average last frost of June 10. Plan your Pumpkin planting based on this frost date — see the calendar above for exact timing.

What planting zone is Mineral County, CO?

Mineral County, Colorado is in USDA Hardiness Zone 5a. The average last spring frost is June 10 and first fall frost is September 13.

🌱

Your Mineral County Garden Planner — Free

A 24-page printable planner built for Mineral 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.

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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: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.