Soil temperature is important for germination in the garden

Hands Planting The Seedlings Into The Ground (Photo: iStock - RomoloTavani)

Home gardeners can take their own soil temperature measurements, says K-State expert

Just in case home gardeners have not really considered the importance of soil temperature, Kansas State University horticulture expert Cynthia Domenghini says you should. Soil temperature, she says, affects germination of many garden foods.

Domenghini said peas can sprout in soil that is 40 degrees Fahrenheit, while lettuce can germinate in 35 F.

“Crops — such as tomatoes, corn and other warm-season veggies — need the soil to be at least 55 F for success,” Domenghini said. “Peppers, cucumbers and melons need even warmer soil.”

The Kansas Mesonet is a resource for guidance on what’s happening below the ground. Domenghini said gardeners can also take their own soil temperature measurements using a soil thermometer, and measuring the soil at least 2.5 inches deep during late morning.

“Find the average soil temperature over five days to determine when the time is right for planting,” Domenghini said. “It is still important to watch the forecast for late season frosts and freezes.”

Domenghini and her colleagues in K-State’s Department of Horticulture and Natural Resources produce a weekly Horticulture Newsletter with tips for maintaining home landscapes and gardens. The newsletter is available to view online or can be delivered by email each week.

Interested persons can also send their garden and yard-related questions to Domenghini at [email protected], or contact your local K-State Research and Extension office.