The Iowa Prairie Seed Calculator will help you create custom seed mixes, taking into consideration such things as seeding method, planting time, and planting site conditions (location within Iowa, soil moisture conditions and erosion potential). You can adjust the seeding rates and select from more than 160 plant species native to Iowa’s tallgrass prairies then bid for the seed at the touch of a button to create a diverse, stable, weed resistant, and long-lived prairie planting.