The Tallgrass 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.

This calculator has been years in the development. It has been field tested on numerous prairie projects here at the University of Northern Iowa (UNI) Tallgrass Prairie Center and on many other public/private prairie projects in Iowa. Recommended species and seeding rates are based on 25 years of planting experience and prairie establishment research. All species listed on the calculator are native to Iowa’s prairies.

The seed calculator offers two cost levels, a premium and economy mix. Ideally, the premium mix would be used for every prairie planting but the reality is that seed cost can be limiting factor. Both levels will produce incredibly diverse, forb rich, stable plant communities fostering pollinator utilization, reducing flooding by increasing water infiltration and interception, virtually eliminating soil erosion and capturing excess nitrogen and phosphorous from going into our waterways. All recommended seed mixes meet and/or exceed Iowa Natural Resource and Conservation Service (NRCS) specifications for seeding natives.

The calculator allows you total freedom to create your own custom seed mix. You have the option to take species out of the mix and/or add new species into the mix. Seeding rates for each species can be easily changed and total seed cost can be recalculated with a click of a button. If you develop a seed mix that varies from the recommended mix and your planting site is enrolled in a conservation program make sure it complies with the seeding guidelines of the corresponding agency.