Sunn Hemp has the reputation of being one of the best soil-building cover crops in the world. It is also an excellent summer deer food plot. Deer love it. This plant grows very fast and typically reaches 6 feet in height in 60 days. It also is a legume so it replenishes the soil with Nitrogen. Within 60 days it typically replenishes the soil with over 100 pounds of Nitrogen and translocates from the subsoil to the topsoil 10 pounds of residual Phosphorus and 80 pounds of residual Potash. It also adds 4 tons of organic matter and suppresses both Root Knot and Reiniform nematodes. The leaves are 30 percent protein. As a reference Alfalfa is only around 20 percent Protein. Sunn hemp will grow on very poor acidic soil. However, as any crop, it will perform better on well drained fertile soil. It does not grow well on water logged soils. The recommended seeding rate is 15 pounds per acre. A well-prepared seed bed is suggested. The seed may be broadcast or drilled in. Seed should be covered 1/4 to 3/4 inches deep.
As with any deer food plot, a mix of several crops is usually better than just one crop. A good mix is 10 pounds of sunn hemp, 4 pounds of Sodbuster Radish (if planting after July 1), 3 pounds of millet or grain sorghum and 3 pounds of sun flowers per acre. Of this mix, the deer will go for the sunn hemp first. As the sunn hemp gets over 4 feet tall the deer love to hide in the sunn hemp while eating the lower sunn hemp leaves and Sodbuster and other crops. Sunn hemp with iron clay peas is another good plot mix. The different mixes you can make with sunn hemp are unlimited. Remember, deer are a lot like people. They like a smorgasbord for a good meal instead of just one item on the menu.
Sunn hemp is a tropical summer legume. It may be planted any time after soils warm up in the spring. It is amazing how fast it grows. It will do its job in 60 days. The longer it grows the more benefits you reap from it. However, you may plant it up until late August and still get phenomenal benefits.
Sunn hemp supplies nutrients for your next crop. The best part of this food plot, besides deer loving it and then growing larger racks and raising healthier fawns, is the fact that it supplies the Nitrogen and organic matter for your winter food plot. When planting your winter food plot, apply about 25 pounds of Nitrogen per acre to get the plot started to a fast early growth and then let it go. You should not need any additional Nitrogen throughout the winter.
The Bow Hunter’s Special: When planting fall deer food plots during September adding 5-7 pounds of sunn hemp to your mix has many benefits. The sunn hemp will quickly attract the deer to your food plot. Sunn hemp planted in September will only get 2-3 feet in height, so you will still be able to see the deer even by Bow Season. The sunn hemp, though not giving much growth, will still enhance the growth of your fall mix, while attracting the deer.