Scope and Location
Food plots should be at least 1,000 square feet if they are to be successful in attracting wildlife. For every 20 acres of land, a food plot of 1/4 to 1/2 acre should suffice. A number of smaller plots is more effective than one very large plot. Food plots should be planted in areas that get about 50 percent sun, preferably morning sun. They should be planted in strips adjacent to woodland or another form of dense cover so that animals will feel safe in the area. Curves or bends in the food plot will also create a sense of safety. Proximity to water is also a good idea.
What to Plant
What you plant will depend on whether you simply want to support the wildlife already on your property, or whether you want to attract a specific species for hunting or sighting. One commercial mix designed to attract deer year-round combines canola, turnips and chicory with four types of perennial clovers and alfalfa. Buckwheat is a versatile warm-weather crop suitable for a variety of purposes. In general a mix of annuals and perennials is good, with an emphasis on annuals until you figure out the right mix for your property and purpose. If you seek to keep wildlife in the area year-round, you will need a mix that spans the seasons. Be sure not to introduce plant species that don't belong in the local ecosystem.
Tips
Once you've scoped the area for your food plot, have the soil tested. Most woodland soil is low in phosphorus and tends to be acidic. Unless your tests indicate otherwise, lime and fertilize the soil before planting. Plow the area to loosen and aerate the soil. Keep records of lime and fertilizer used, annual rainfall and other variables so you can refine your food plots from year to year. If hunting is your objective, do not over hunt a given food plot.
Public Resources
One of your best resources is the local cooperative extension office. The cooperative extension system is a nationwide educational network that partners with the National Institute of Food and Agriculture. State offices are housed in the local land-grant university. They can provide soil tests and other expertise regarding your food plot. The U.S. Fish and Wildllife Service and the local State Gaming Commission are also excellent resources.