DEVILS LAKE – North Dakota State University Extension recommended long-term establishment of pinto beans at 70,000 plants per acre and black and white beans at 90,000 plants per acre in wide rows (30 inches).
However, based on an annual dry bean g
rower survey, farmers who grow black and navy beans use larger plant populations and narrower rows, says NDSU Extension cropping systems specialist Greg Endres. A lesser trend exists for pinto bean growers.
“With the support of the Northarvest Bean Growers Association, the NDSU has conducted field trials over the past decade to examine the potential for increased yield with the three types of dry bean market impacted by these two factors. plant establishment,” says Endres.
Black and navy bean research trials were conducted in eastern North Dakota near Carrington, Park River and Prosper from 2014 to 2018 that included targeted early season populations of 90,000, 110,000 and 130,000 plants per acre with spacings of 14, 18 or 21 and 28 inches.
Black bean seed yield was 13-14% higher with narrow row spacing (14 inches) compared to wide rows (28 inches). The average plant population of around 100,000 to 150,000 plants per acre provided a similar yield. Narrow rows with white bean plant populations of over 115,000 plants per acre increased yield by 24% to 28% over wide rows, with just over 90,000 plants per acre.
From 2018 to 2021, Carrington and Langdon Research Extension Centers conducted a pinto bean field study comparing mid-range (18 or 21 inches) to wide (28 or 30 inches) row spacing and targeted stands of 50,000, 70,000 and 90,000 plants per acre. Seed yield was mainly affected by row spacing. The average yield increase was 17% with intermediate row spacing and plant populations of about 65,000 or 84,000 plants per acre compared to wide rows.
Pinto bean row spacing assessed as a single factor in 11 trials (Carrington, Langdon, and Minot; 2011 to 2013 and 2018 to 2021) indicates a 20% yield increase with 15 to 22 inch rows compared to wide rows. Plant population assessed as a single factor in four trials (Carrington and Langdon; 2018 to 2021) indicates a 5% yield increase with a population of 87,000 plants per acre compared to a similar population at the standard density of 70 000 plants per acre.
A publication showcasing pinto bean research will be available later in May. For more information on the most recent dry bean grower survey and research on black and navy beans, search for these publications:
“2021 Survey of Dry Bean Growers on Production, Pest Issues, and Pesticide Use in Minnesota and North Dakota” at https://www.ndsu.edu/agriculture/extension/publications/2021 -dry-bean-grower-survey-production-pest -problems-and-use-of-pesticides
“Black and Navy Bean Response to Row Spacing and Plant Population in Eastern North Dakota” at https://www.ndsu.edu/agriculture/ag-hub/ag-topics/crop -production/crops/dry-edible-beans/black-and-navy-bean-response-line-spacing