The wide window of planting and excessive rain this season will make determining when to dig peanuts a "field-by-field decision," says North Carolina’s Extension peanut specialist.
Digging peanuts is one of the biggest management decisions farmers make. Too early or too late can cause problems.
"It’s a balancing act," says David Jordan, North Carolina State University Extension peanut specialist.
Managing the balancing act at harvest this season will be particularly important for peanut farmers because of the lateness of the crop, he says.
While much depends on what happens in late August through October, "until you dig them and get them out of the field, anything can happen," Jordan says.
Excessive rains delayed planting in the spring and will ultimately push back harvest to some degree. "One of the biggest challenges will be deciding when to dig.
"Although we planted late in some instances, we haven’t had our typical dry spells that cause breaks in maturity this year," Jordan says. "I’m thinking that maturity ought to be compact, but too much moisture may have slowed down the growth in some fields. It’s been very cloudy during the growing season."
Peanuts grow indeterminate and underground, making a harvest decision difficult at best. Extension services in peanut states offer harvesting clinics where farmers can bring in a representative sample of a field. Using high-pressure water and glass beads, county agents place peanuts in a cylinder that peels the top layer off the pods to reveal maturity. The color of mesocarp of the peanut pod gives a clue to its maturity.
"Not all pods are going to be mature," Jordan says. "The key is to pick a time to dig based on when the largest number of the sample is mature."
Grades and yields are at stake if you dig too soon. And you can lose a lot of yield in the field if you wait too long to harvest, Jordan points out.
He’s advising growers to bring a sample of 150 pods per field to pod maturity clinics in peanut counties in North Carolina beginning in mid- to late-September. "Pull off the pods that will make it into the trailer after you combine," Jordan says. "It takes about three minutes to run a sample at the clinic and few more than five minutes to lay it out on a board to determine maturity. The big thing is it tells farmers which fields to go to first."
Nighttime temperatures in late September and early October in the upper Southeast begin to take a dive into the 60-degrees F range and 70-degrees F range, even though daytime temperatures may be in the mid- to-high 80-degres F. "The plants cool down and growing begins to diminish to some degree; this is when it is hard to make up time lost early in the season," Jordan says.
"Patience at harvest is critical, but no one ever said patience is easy to come by in the fall when the crop is still out there," Jordan says. "Still, a week can make a big difference in terms of yield and market grades."