It is important to be an astute buyer when purchasing prairie seed. Seed is often the most expensive part of a planting project, but ‘shopping’ for a prairie seed mix can be complicated. Prairie nurseries for example, offer many prepackaged prairie seed mixes for retail sale. These mixes are marketed to a wide array of projects and customers; some are specially developed for use only in detention basins or along roadsides, or to attract pollinators and promote conservation. There are prepackaged seed mixes for various soil moisture conditions, tall or short plants, and many with varying amounts of grasses and wildflowers based upon market demand for certain species. Every prepackaged seed mix has a different suite of species, different seeding rates and varied retail pricing, making it impossible to do a fair comparison among prepackaged seed mixes to find the best value. This is where the Tallgrass Prairie Seed Calculator can be invaluable.

Once you have developed a custom seed mix with the calculator, your custom seed mix can be automatically emailed to multiple prairie seed nurseries for competitive bids online. Not only does the seed calculator provide you with the tools to create the best custom mix possible for your planting site, it jump starts the process of finding that seed at the best price available (prices are updated annually). The seed calculator bidding software gives the nurseries an opportunity to fill your order on a competitive priced basis. There are some caveats with online competitive bidding you’ll need to be aware of, including:

  1. Don’t be disappointed if some nurseries don’t respond to your bid request. Keep in mind that asking a nursery for a bid is more work for them without any guarantee that you will buy their seed. It may not be worth their time to respond on small orders.
  2. Some bids returned to you may have different units of measure as it relates to cost. The seed bid asks for seed cost per ounce but you may get a seed bid in seed cost per pound or a total seed cost by species. This will require converting the units on some bids to standardize bid costs so that they can be compared. Here are a two ways to go about this:
    • Compare total cost of each species among bids (which is the easiest way to compare).
    • Convert total cost of each species to cost per ounce PLS for comparison. To convert cost per pound to cost per ounce, divide the total cost (of each species) listed on the vendor bid sheet by PLS ounces needed of that species listed on your bid sheet.
  3. Be prepared to buy seed from more than one nursery if you want to get the best price. Seed availability varies depending on what time of year the seed is purchased. I have found that seed availability is lower when purchased in late summer into early fall and highest in the winter months. If you do try to purchase seed in early fall for a fall planting and there are many species not available at that time, you might want to consider purchasing seed in the winter and moving your seeding time to the following spring.
  4. Some seed nurseries will offer to substitute species for the species requested on the bid sheet, but which are unavailable. We recommend not using substitute species for they may not be appropriate for the soil moisture conditions and/or not within the species historic range of your planting site. There are a few ways to handle substitute species:
    • Buy more seed of an available species to compensate for the unavailable species.
    • Contact other nurseries listed on the seed mix sheet to see if they have seed available for those species.
    • Substitute unavailable species with species listed on the seed mix sheet generated by the calculator that were not included in the original seed mix.
    • Just leave the few unavailable species out of the seed mix. This option should only be used if it involves just a few species and if each species has a seeding rate of 0.1 seeds per square foot or less. We would like to see all recommended species included in the seed mix, however, in reality leaving a few species out of the seed mix should not reduce the overall seeding rate of 40 seeds per square foot and not have significant impact on stand diversity.