Variety selection, attention to planting time and seeding rate, and proper fertility are part of the recipe for success for Oklahoma peanut growers in 2008.
Chad Godsey, Oklahoma Extension peanut specialist, said decisions farmers make early in the season will determine success at harvest.
“Planting decisions are important,” he said.
Variety selection may be the first option farmers consider, and Godsey said looking for a variety with disease resistance is a good starting point. “Runner-type peanuts have the most complete disease package, especially for leafspot,” Godsey said during the recent Oklahoma Peanut Expo in Lone Wolf.
He recommended farmers plant Virginia types only “in rotation or on new peanut ground and not on land with a long history of peanut diseases.”
He said farmers who plant Spanish peanuts should “stay on top of leafspot control.”
Godsey said growers should look at a variety's “history of performance,” and said farmers should use several varieties for disease management, planting dates and harvest timing.
He also suggested they look at state variety trials to see how the standard lines compete with each other and how newcomers stack up.
Regardless of variety and planting date, Godsey believes rotation should be the key to peanut farmers' management strategy. “Rotation with a grass crop is best,” he said. “Cotton is also a good option. And two years out of peanuts is ideal; one is not enough.”
He said some farmers might be tempted to add soybeans to a rotation plan, especially with soybean prices at record or near-record highs. Not a good idea. He said soybeans and peanuts share some diseases and that weed control may be tougher with peanuts behind soybeans. “Don't plant soybeans directly in front of peanuts. You need a grass crop in a peanut rotation.”
Godsey said rotation trials show a significant yield advantage, up to 500 pounds per acre, in a peanut crop following a good rotation option. “We saw no real benefit with cotton rotation of only one year. With two years in cotton, the benefit was significant. That test verifies the need for rotation.”
Growers should not use a calendar to schedule peanut planting dates. “Soil temperature at a four-inch depth should be at 65 degrees F for three consecutive days at 7 a.m. Check the Mesonet at agweather.mesonet.org/soil/default.html. Use that instead of a calendar date.”
He said peanut plants need temperatures ranging between 77 degrees F and 86 degrees F for rapid growth.
He recommended plant populations of five to six per foot of row for Spanish and four per foot of row for runners and Virginias.
“We recommend an inoculant regardless of field history. The cost of adding inoculant, considering the higher number of rhizobium nodules gained, is cheap compared to other costs. It's inexpensive insurance.”
Growers should check other products they are applying to determine compatibility with inoculants. “Read the labels.”
He said a basic approach to fertility starts with a soil test. “Fertilize the preceding crop for phosphorus and potassium, but if soil tests indicate deficiency, apply necessary amounts, but not in the seed furrow.” He recommends application in a two-inch band two inches from the row.
“A starter fertilizer with 10 to 20 pounds of nitrogen is important. Again, don't apply to the seed but put it to the side.” He said tests indicate a yield response to starter fertilizer applications. “Often, farmers will have nitrogen in the soil from a previous crop, so take that into account.”
Calcium is “required in high amounts for peanuts. If tests indicate less than 600 pounds of calcium per acre, apply it. We recommend applying calcium to Virginia peanuts regardless of soil test results.”
He said calcium is important for runner and Spanish peanuts, but is not as critical as for Virginias. “For runners and Spanish, 600 to 650 pounds per acre is adequate.”