When Should I Plant Sweet Corn in Utah?
Quick Answer
Sweet corn should be planted on your area's average last spring frost date or shortly after, once the soil has warmed to 60 °F or higher. Don’t plant too early. Corn struggles to emerge in wet, cold soil, and young plants can be damaged by frost.
Spring Last-Frost Dates for Utah Towns and Cities:
- Alpine - May 20
- Blanding - May 13
- Bountiful (Val Verda) - April 17
- Cedar City - May 10
- Delta - May 17
- Farmington - May 5
- Fillmore - May 16
- Huntsville - June 11
- Kanab - May 7
- Lake Town - June 15
- Logan - May 14
- Midvale - May 13
- Morgan - June 6
- Moroni - June 1
- Ogden - May 1
- Park City - June 9
- Price - May 12
- Provo (Airport) - May 21
- Provo (BYU) - May 1
- Roosevelt - May 18
- Salt Lake City (Airport) - April 26
- Salt Lake City (U of U) - May 1
- Salt Lake City (Cottonwood) - April 30
- Spanish Fork - May 1
- St. George - April 6
- Tooele - May 7
- Tremonton - May 3
Visit the Utah Climate Center’s Utah Freeze Dates page for a more thorough database of average last-freeze dates.
How Long Does It Take Sweet Corn To Grow?
Depending on the variety, sweet corn matures in 60-90 days. Even in the same area, growing seasons and planting dates can differ. Gardens in town or on a bench tend to have longer seasons than those in lower spots.
How Can I Extend the Growing Season for Sweet Corn?
To ensure fresh corn the whole season long, sow additional corn every 10 days to two weeks until early July. You can also start a plant more once the first leaf unfurls on the planted batch.
How Late Can I Plant Sweet Corn?
Plant your first crop no later than early June. Planting later risks missing the harvest window before the first fall frost.
How to Plant Sweet Corn
What Type of Soil Is Best for Growing Sweet Corn?
Sweet corn thrives in fertile, well-drained soil.
How To Prep the Soil for Sweet Corn?
Test your soil before planting to see how much fertilizer it needs. Mix fertilizer into the top 6 inches of the soil. When using compost, use fully composted organic matter spread no more than 1 inch thick for every 100 square feet of garden.
How Much Sweet Corn Seed Do I Need?
You'll need 3-4 ounces of seed for every 100 feet of row. Plant in blocks of at least three rows instead of one long row. This allows for better pollination and produces more ears. 10-15 pounds of seed produce abou an acre of sweet corn.
How Far Apart Should I Plant Sweet Corn?
Sow seeds about 1 inch deep and 7-8 inches apart, with rows 28-32 inches apart.
Should I Water Corn Right After Planting?
Ensure the seedbed is consistently moist at planting and until the seedlings emerge. That usually means watering the furrow before sowing seeds or the top of the soil after covering them.
References
- Suggested Vegetable Planting Dates For the Wasatch Front by Shawn Olsen, USU Extension Agent
- How to Grow Sweet Corn in Your Garden by Dan Drost, Retired USU Extension Vegetable Specialist
- Utah Vegetable Production Guide: Sweet Corn - Planting, Spacing & Thinning by Nick Volesky, Mair Murray, Amelia Olds, and Bridger Carey, USU Extension Plant Health
- Gardener's Almanac Monthly Gardening Checklist by Jaydee Gunnell, USU Extension Professor
- How to Plant Corn presented by Ron Patterson, Former USU Extension Carbon County Agent
- Plant Now or Wait by Taun Beddes, USU Extension Associate Horticulture Professor, and Julene Reese, Extension Public Relations Specialist
Authors
Adapted from USU Extension publications and video by Shawn Olsen, Dan Drost, Nick Volesky, Mair Murray, Amelia Olds, Bridger Carey, Jaydee Gunnell, Ron Patterson, Taun Beddes, and Julene Reese