Published on Wednesday, May 01, 2019
Maximizing soybean yield is a simple concept…grow as many harvestable soybeans per acre as possible. What is not so simple is the complex dance we play with Mother Nature who has great influence over the best management decisions required to obtain maximum yields. For multiple years, Beck’s PFR has promoted increasing returns on investment (ROI) by lowering soybean seeding rates.
This concept works because your soybean yield potential directly correlates with the number of nodes per acre, not the number of plants per acre. In early planting situations, lower populations compensate by branching and producing more nodes per plant, ultimately generating similar numbers of nodes per acre compared to higher seeding rates.
The increase in ROI is simply a function of seed cost savings. However, this only works in early planting situations. Soybeans are photo-period sensitive, which means that the transition from the vegetative to reproductive growth stage is driven largely by the shorter day periods following summer solstice on June 21.
Planting earlier allows for more vegetative growth (node production) prior to switching into the reproduction stage. Because vegetative growth will be limited in delayed planting situations, higher populations are therefore required to maximize your nodes per acre (yield potential). An extreme example of this is demonstrated by the economic optimal seeding rate (EOSR) in the early July planted double-crop situation shown below.
As a general rule of thumb, in order to maximize yield potential in late-planted soybean situations, I recommend increasing seeding rates by 10,000 seeds/A. for every week that planting is delayed past the first week of May. For example, in North Central Indiana, if planting is delayed until the last week of May, I would increase the target seeding rate by 30,000 seeds/A.
If you have any questions about seeding rates or delayed planting scenarios, please contact me or your local seed advisor or dealer.
Author: Travis Burnett
Categories: Agronomy, Agronomy Talk
Tags: planting, Soybean Seeding Rate, Delayed planting, double crops