Spring oats Planting Dates in Illinois

Usual spring oats planting and harvest periods in Illinois, shown as ranges with their source. Use them to frame a plan, then adjust for your own frost dates and soil temperature.

Spring oats dates in Illinois
Activity	Window	Source	Last verified
Planting	Mar 20 to May 12 usual (most active Mar 29 to Apr 30)	source	2026-11-11
Harvest	Jul 4 to Aug 13 usual (most active Jul 14 to Aug 7)	source	2026-11-11

Spring oats calendar for Illinois
Item	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Planting			Planting window, most active in March	Planting window, most active in April	Planting window in May
Harvest							Harvest window, most active in July	Harvest window, most active in August

What these dates mean in Illinois

Planting usually runs about 54 days, from Mar 20 to May 12.

That start date is about 11 days earlier than the middle of the 24 places in this data set that report spring oats planting dates (Mar 31).

Harvest usually runs about 41 days, from Jul 4 to Aug 13.

From the start of the planting window to the start of the harvest window is about 106 days in Illinois, a rough guide to how long the crop occupies the bed or field.

Frost-date caveat: these are published ranges for Illinois. A northern or high-elevation site will run later than a southern or low one, and a cold wet spring can push planting past the window. Frost dates and local conditions vary; NASS state-level usual dates from 20-year progress data (Oct 2010 edition), begin ~5% and end ~95% complete. Check your last spring frost and soil temperature, and confirm with your county extension office.

Related guides

Oats Planting Calendar

Spring oats dates in other places

Other crops in Illinois

Last reviewed: November 2026. Source: USDA NASS, Field Crops Usual Planting and Harvesting Dates (October 2010 edition, copy hosted by Cornell University Mann Library). Dates are the usual start and end of the period when about 5% to 95% of the crop is planted or harvested, from long-run state progress data. They are historic averages, not a forecast.