More on wildflower mixtures and plantings:Our wildflower mixtures are formulated on the basis of climatic conditions (rainfall, temperature range, humidity) and elevation. Most species in our mixtures adapt readily to different soil types, provided climate and elevation are suitable. Annuals have been included to establish cover quickly and to give color the first year; some may produce new plants the following year (the biennials may also reseed). Perennial plants live for more than two years, and most flower from the second year onward.These mixtures are blended to give the widest possible range of colors and periods of bloom. Very few wildflowers bloom continually throughout the season; therefore, we have included Spring, Summer and Fall-blooming species in each mixture. Colors include blue, purple, red, white, yellow and pink. Mix heights vary from 10 in. to 8 ft.In general, our mixtures are formulated to contain approximately equal numbers of seeds of each species. This varies somewhat because of costs, availability and/or climatic conditions. Mixtures may vary occasionally from the indicated listing, based on availability of individual species.Seed Quality:Most wildflower seeds and mixtures have a purity of 95 to 99% and total viable seed percentages of between 70 to 95%. The total viable seed percent is the germination percent, plus the hard seed or dormant seed percent. Hard seeds have impermeable seed coats and cannot imbibe water during seed testing. Dormant seeds are viable seeds that have specific physical or physiological conditions that prevent the seed from germinating at the time of seed testing. The PLS (Pure Live Seed) is obtained by multiplying the percent purity by the percent total viable seed and then dividing by 100.Uses of Grasses:Wildflowers can be sown alone or with grasses. For most areas of the United States, we recommend using one of our native grass mixtures. For specific requirements, individual species may be preferred. Hard Fescue or Sheep Fescue work well in most areas of the United States. However, in the southeastern states of Alabama, Florida, Georgia, Louisiana, Mississippi and South Carolina, we recommend warm-season grasses; Hard and Sheep Fescue will not thrive in these climates.Warm-season grasses to consider include Gramas, Buffalo Grass and Bluestems. These grasses grow very slowly and are planted for aesthetic and ecological reasons rather than prompt stabilization of soil.Aggressive grasses should be avoided because they will crowd out most wildflowers; these grasses include Kentucky Bluegrass, Smooth Brome, Crested Wheatgrass, Bermuda Grass, and Annual Rye. If wildflowers must be used with these grasses, the flowers should be planted in high-density patches as accents to the grassed areas. Or the flowers may be sown with the grasses if the planting rates of the grasses are reduced significantly.