As you drive the highway from Moultrie, Ga., to the Sunbelt Expo, look to your left as you approach the show site. You’ll see a bright green field of short growing forage plants sporting brilliant yellow flowers.
What you are seeing is a field of perennial peanuts. These peanuts don’t produce nuts like the better known field peanuts. No. These peanuts are grown for forage and their nutritious stems and leaves.
Perennial peanuts produce high-quality legume forage. This forage can be grazed or fed to horses, dairy and beef cattle, hogs, goats, sheep and rabbits. It can be stored as a dry hay or silage and is an ideal substitute for imported alfalfa. In Florida, the perennial peanut is known as Florida’s alfalfa.
As a hay crop on a per-acre basis, perennial peanuts can even be more profitable than field peanuts and other field crops.
Once established, these forage peanuts are persistent. Under good growing conditions, perennial peanuts can produce three to five tons of forage per acre per year.
The perennial peanut stand at Expo is one of the oldest in south Georgia. The Expo farm also hosts an annual summer field day for perennial peanut growers in north Florida and south Georgia.
A tropical plant, the perennial peanut can be killed by cold weather. It is only adapted to the southern portions of Gulf Coast states. This roughly corresponds to areas 8a, 8b and 9 as shown on a USDA plant hardiness zone map. Perennial peanuts are hardy plants and can grow well in dry, sandy soils.
Generally, these peanuts can be grown with no insecticides or fungicides, and the fertility requirements are similar to those for field peanuts.
Getting a stand can be a challenge. The crop is planted using underground stems called rhizomes. These rhizomes are dug with a sprig harvester and then are planted with a sprig planter, like those used for establishing hybrid bermudagrass. Planting usually takes place during the winter or early spring.
Good weed control and irrigation are important for successful stand establishment.
Though perennial peanuts have few natural pests, there is one condition that has severely affected the stand at the Expo farm. It’s called peanut stunt virus. In 2003, Expo farm manager Darrell Williams first noticed small areas of the perennial peanuts with dead and stunted plants. Since then, the virus has spread to all of the Expo’s perennial peanut fields.
Green peach aphids spread the disease to the peanut plants. The virus also persists from year to year in the roots and rhizomes of the perennial peanuts. It shows up on leaves that are malformed and curled up at the edges. Infected leaves may show a pale green or even yellow color. The virus can also over-winter in wild or forage legumes.
After the virus spread, Williams saw perennial peanut hay yields drop in 2005 by more than half of what they had been in previous years. Some fields could be cut only once for hay last year. He notes that weather, fertility and weed problems may have also contributed to the last year’s low yields.
In north Florida, peanut stunt virus has been seen for about 10 years on perennial peanuts. University of Florida forage scientists say the disease seems worse during the first year or so of infection, with stunting and yield reductions less in later years. The stunt virus doesn’t automatically mean low yields. Some of the stunt virus-infected perennial peanut plots in North Florida still yield four or more tons of hay per acre per year.
There is no known control for peanut stunt virus. Until one is found, the best approach seems to be making sure that liming, fertilizer and weed control needs of the crop are met. Doing so will help insure that no additional stress is placed on perennial peanuts that could exacerbate losses from the virus.