Navy Bean Yield Response to Rows Spacing and Plant Population (05/12/22)
Navy dry edible bean (Phaseolus vulgaris L.) is the fourth most commonly grown market class in North Dakota and Minnesota (12.6% of total bean acres), based on the 2021 Northarvest bean grower survey. North Dakota State University’s current recommendation is to establish 90,000 – 115,000 navy bean plants per acre but the 2021 survey indicates 66% of growers planted at a seeding rate of 110,000 to 129,000 seeds per acre. Also, the survey indicates 68% of navy bean growers use rows 21-25 inches wide.
A study in Carrington, North Dakota with navy bean conducted in 1999-2000 indicated no seed yield response among small-seeded bean planting rates of 90,000, 105,000, and 120,000 pure live seeds (PLS) per acre, and yield increased in one of two years with 7- versus 30-inch rows. A North Dakota study reexamined the interaction of navy bean row spacing and plant population to identify potential navy bean seed yield increase with narrow rows and higher plant populations. ‘Avalanche’ navy bean was planted in 14-, 21- and 28-inch rows at 100,000, 125,000 and 150,000 PLS per acre at Carrington in 2014 and 2016-17.
Navy bean seed yield, averaged across three site-years at Carrington, was statistically different with the two-factor interaction (Table 1). Averaged across three years and rows, plant population was 92,600, 116,800 and 139,800 plants per acre with the low to high planting rates, respectively. Highest yield was achieved at 2,790 and 2,660 lb. per acre with 14-inch rows and the high and medium plant populations, respectively. The combination of 14-inch rows and plant populations of greater than 115,000 plants per acre increased yield 24% to 28% compared to 28-inch rows with slightly more than 90,000 plants per acre.
Among the three plant populations, navy bean seed yield increased 10% to 23% with 21-inch rows compared to 28-inch rows. Within 21- and 28-inch rows, yield did not increase with increased plant populations. For more information see the April 2022 revised Extension publication Black and Navy bean response to row spacing and population.
The study results support current navy bean grower trends of reducing row width and increasing plant populations, and indicates a need to revise NDSU recommendations for navy bean plant establishment.
Extension Agronomist Broadleaf Crops
Extension Cropping Systems Specialist
