A meadow planting, incorporating wildflowers and native grasses, offers several advantages over turf or non-native species. Natives have evolved in the local environment, adapting to the climate, natural soil conditions and water supply. Wildflowers and native warm-season grasses are either perennial or self-sowing. Combine their adaptation and longevity and you have a landscape that won't need the constant attention needed by one full of introduced species. In addition, song birds, butterflies and other wildlife flock to their natural food and shelter sources when they're available. A wildflower meadow might be as small as a border on a suburban lot, or several acres of rural property.
Kill all existing vegetation either chemically or by soil sterilization. For large projects, chemical treatment with a non-selective herbicide like glysophate is the most effective approach. For a smaller area, cover the ground with something that light can't penetrate. Heavy black plastic works well. This should be done in the spring or early summer before the area is to be planted in the fall.
Remove all plant residue. For small projects, a rake will do the job. On large projects, burn the residue if permitted in your area or use a tractor with a landscape rake. Once the soil is exposed, weed and grass seeds will likely germinate. Repeat whichever process you used in Step 1 to kill the new sprouts.
Scratch the soil surface to a depth of 1 inch. Use a garden tiller for small projects or a tractor with a disc or landscape rake for large projects. Do not till deep. Doing so will bring up more weed and grass seeds. Loosen the soil shortly after the repeat kill. If weather during the target planting period cooperates, repeat just before planting.
Buy seed based on your conditions, landscaping goals and plant compatibility. The Missouri Department of Conservation and native seed sources recommend planting about 11 lbs. of blended seed to the acre. While it's tempting to go heavy on wildflowers, don't skimp on the grasses. Native grasses support tall, leggy flowers in the meadow and add visual interest when winter has sent all the flowers into dormancy. Sideoats grama, broom sedge, little bluestem and prairie dropseed are among the native warm-season grasses that blend well with wildflowers.
Sow the seeds between the middle of November and the middle of January. Most wildflower seeds need to be exposed to a freeze-thaw cycle before they will germinate. Late-fall to early-winter planting insures this. Blend the seed with an inert carrier, such as sawdust, to aid in even distribution. The recommended 11 lbs. per acre divides out to 1/4 lb. per 1,000 square feet. Add 2 lbs. of sawdust to 1/4 lb. of seed, mix thoroughly and spread over 1,000 square feet.
Roll the planted area with a weighted roller to insure seed to soil contact. Rain, ice, snow and cold temperatures do the rest of the work, cracking seed coats and working the seeds deep into the soil.
Mow the area to a height of 6 inches whenever the plants are above 12 inches tall through the first growing year. This will usually mean mowing three times. The second year, mow only if weeds are present. From year 3 forward, burning once a year or every other year will be the only maintenance needed.