Mississippi peanut farmers usually try to hit a late April to early mid-May window to get their peanuts in the ground, but only 10 percent of the state’s total acreage had been planted by that time this season. A wet, cool spring delayed planting and Dr. Brendan Zurweller, Extension peanut specialist, Mississippi State University, reports most peanuts did not get planted until the third and fourth week of May.

Peanuts are a long-maturing crop. “Late-planted peanuts usher in greater harvest risks,” says Zurweller, speaking at the recent Mississippi Agricultural Industry Council’s 59^th annual convention in Orange Beach, Ala. “That risk can be increased if Mother Nature delivers an especially cool and wet fall.”

Growing degree day accumulations typically start slowing down around Oct. 1, and really slow by Oct. 15. “We will have a large amount of peanut acreage being harvested later into the fall this year with the later planting dates,” says Zurweller. “That’s one reason we may see an acreage decrease this year. Some growers in the northern half of the state who usually dedicate 700 to 900 acres to the crop reduced their acreage to lower their risk of possible harvest complications.”

Canopy health will be critical this fall, so managing disease to help protect the crop during those last few weeks of maturation could be essential. “Soilborne diseases are starting to pick up. I had some calls last month from growers in the hill country about early-season Southern blight, which attacks the crown and below ground parts of peanuts,” says Zurweller. “Dr. Alan Henn, our plant pathologist, has spoken to some Arkansas consultants who reported some Southern blight in their areas as well.”

Weed management and irrigation

It has been a wet year in many areas, but the cleanest fields are on farms where growers started clean and stayed clean. “In fields where there has been a gap between field preparation and planting, we are seeing bigger weeds and more escapes after the initial burndown,” says Zurweller. “We don’t have herbicide-resistant traits and our chemistry options are more limited in peanuts.”

Most Mississippi peanut acreage is dryland and usually smaller acreage on a per-farm basis. Zurweller advises growers to be strategic when making herbicide applications. “One example of this is timing post-emergence residual herbicides before precipitation events to ensure you get good activity. I would consider applying a post-emergence residual herbicide to a clean field before a rain to help keep it clean. It could end up saving a herbicide application later in the season,” says Zurweller. “That’s an example of taking advantage of the weather.”

Staying clean will help avoid some of the hotter tank mixes that are sometimes needed when weeds start choking the crop. “If you do have to make those hot mixes, it’s best to make those applications early,” says Zurweller. “These applications during blooming and later reproductive stages increase the risk of yield loss.”

An example of this in peanuts is the use of paraquat. As rates of use increase, the risk of yield declines from the application increase; but the earlier you can make the application, the better. “I also advise mixing bentazon in with the paraquat,” says Zurweller. “There has been a lot of research showing it reduces the activity a great deal, and you can avoid having a yield decline.”

Forty-five percent of the U.S. peanut acreage is irrigated, but 75 percent of Mississippi’s peanut acreage is produced on dryland operations. “If you have irrigation, you’ll see on average a 700- to 800-pound yield increase,” says Zurweller. “It usually takes about 135 to 145 days for peanuts to get to harvest maturity, but the water demand and sensitivity of peanuts to drought is not the same throughout its development. The crop can stand a little more drought during early bloom, but the most critical time to avoid drought stress is when the plants start pegging and developing pods. When the crop reaches around 110 days, the demand for water and the sensitivity to drought tapers off.”