How is South Dakota's climate changing?

South Dakota's climate is warming, with first freeze dates arriving 1.4 days later per decade on average. This has extended the state's growing season by over 18 days since the late 1800s.

What are the challenges posed by the later first freezes in South Dakota?

The later first freezes increase the risk of wildfires, as well as problems with pests like grasshoppers and mosquitoes, and more persistent weeds that can produce more seeds before dying off.

Home / Environment / South Dakota's Expanding Growing Season Brings Evolving Risks

South Dakota's Expanding Growing Season Brings Evolving Risks

Q: What impact has the longer growing season had on South Dakota's corn production?

The extended growing season has allowed South Dakota farmers to harvest over 1 billion bushels of corn this year, the largest amount in state history.

14 Nov, 2025

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Summary

First freeze dates in South Dakota trending 1.4 days later per decade
Longer growing season boosts corn production to record levels
Later freezes increase wildfire, pest, and weed management challenges

South Dakota's Expanding Growing Season Brings Evolving Risks

According to the latest data, South Dakota's growing season has been steadily expanding, with first freeze dates now arriving 12 days later in Sioux Falls, 13 days later in Mitchell, and 7 days later in Rapid City compared to the 1970s. Statewide, the trend is 1.4 days later per decade, a change consistent with climate models projecting the effects of rising greenhouse gas emissions.

This extended growing season has allowed South Dakota farmers to harvest over 1 billion bushels of corn this year, the largest amount in state history. However, the later first freezes also bring new challenges, including an elevated risk of wildfires, as well as increased problems with pests and weeds that can persist longer without a "killing frost."