The Iowa Prairie Seed Calculator designs a custom blend of grasses, sedges, legumes and other forbs fine-tuned for your county and five different soil moisture classes. You have complete control to add or substract species as your budget allows, and it also provides an easy way to send the seed mix out for bid. Try this out and tell us what you think. For a demonstration video of the Seed Calculator, click here.
A new research report helps to answer some basic questions about the importance of a well-designed seed mix and establishment mowing. A successful prairie planting must be durable, diverse, and cost-effective. In 2015, the TPC compared a widely-used Economy mix ($130/ac, 21 species, 3:1 grass: forbs), our custom-designed Diversity mix ($290/ac, 71 spp., 1:1) and a popular Pollinator mix ($370/ac, 38 spp, 1:3 grasses:forbs). All mixes met or exceeded NRCS specifications and were sown at ~430 seeds/m2. Plots were replicated and randomized in a proper experimental design.
By the conclusion of the first growing season, the Diversity mix had 1.9x more species and 4x more seedlings than the Pollinator mix. The Economy mix was slightly less costly than Diversity, but had much lower species diversity.
Wildflower species were not only more numerous, but grew larger in mowed plots (p<.05). In the photo below, grey-headed coneflower plants were 13x larger in the mowed plots. Larger plants are destined to get a head start and out-compete weeds in Year 2. Mowing increased cost-effectiveness by three-fold.
Taken together, mowed diversity plots cost $1.22 per thousand plants, while unmowed pollinator mix plots cost over $17.00 per thousand plants.