When to plant Corn in Denver County, CO
In Denver County, Corn is a single-season spring crop — there's no second fall window. Plant May 21–June 11 for an 60–100-day harvest, finishing well before the September 26 first frost.
When to Plant Corn in Denver County, CO
Corn is a warm-season grass grown for its sweet ears, which are best eaten soon after harvest. It is wind-pollinated and must be planted in blocks for good kernel fill.
Denver County, Colorado is in USDA Zone 6a. The average last spring frost is May 14 and the first fall frost is September 26, giving you a growing season of approximately 135 days.
At an elevation of 6,818 feet, Denver County receives approximately 20.5 inches of rainfall annually with predominantly loam soil. Summer highs average 85°F, providing good warmth for Corn during the growing season.
Denver County Soil Profile
Soil Type
Loam
Soil pH
6.0-7.0
Drainage
Well Drained
How Much Corn to Grow
For a family of 4, plant approximately 60 corn plants in about 120 sq ft. In Denver County's 135-day season, you'll have plenty of time for a full harvest. Plan your garden layout →
Corn Planting Timeline — Denver County, CO
Corn Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | May 21 | May 21 – Jun 11 |
| Harvest | July 23 | Jul 23 – Sep 17 |
Plant 1" deep · 12" apart · Rows 36" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Direct Sow |
| June | Direct Sow |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
60–100 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 6a
📆 Growing Season
135 days in Denver County
Growing Tips for Denver County
Plant in blocks of at least 4 rows rather than single rows for proper pollination. Direct sow after soil reaches 60F. Side-dress with nitrogen when plants are knee-high.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Corn in Other Locations
Frequently Asked Questions
When should I plant Corn in Denver County, CO?
Denver County is in Zone 6a with an average last frost of May 14. Plan your Corn planting based on this frost date — see the calendar above for exact timing.
What planting zone is Denver County, CO?
Denver County, Colorado is in USDA Hardiness Zone 6a. The average last spring frost is May 14 and first fall frost is September 26.
When should I plant Corn in Denver County, CO?
In Denver County, CO, plant Corn after the last frost (around May 14) and before the first frost (around September 26). Best results when soil holds above 50°F.
What growing zone is Denver County, CO for Corn?
Denver County sits in USDA Zone 6a. Corn grows reliably in zones 3a through 11b, so it's a good fit here.
Can Corn grow in Denver County's climate?
Yes — Corn grows well in Denver County's temperate climate. Denver County averages a 135-day frost-free season, with last frost around May 14 and first frost around September 26.
Your Denver County Garden Planner — Free
A 22-page printable planner built for Denver County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.