Listen to the KTIC Radio Extension Corner:
This is Dr. Nathan Mueller, your local agronomist with Nebraska Extension for Dodge and Washington counties. As we move into the month of June, we usually start to wonder if we should make any changes to our normal soybean management, such as changing relative maturity, custom planting, or seeding rates. As the next weather systems moves in today and tonight bringing more chances for rain, I have 4 things for you to consider for late-planted soybeans.
First, stick with your normal maturity group or relative maturity rating varieties until after June 15. A 2003 to 2004 planting date study in Lincoln looked at the average response of 14 varieties ranging from a 3.0 to 3.9 relative maturity. The study found that due to soybeans being photoperiod sensitive, flowering and maturity was similar among plantings dates. For example, an end-of-May planted soybean only matured 1 to 3 days sooner than mid-June planted soybean crop. A 2013 variety trial conducted in southeast South Dakota on 55 varieties showed that by reducing the relative maturity by 1 unit from a 2.8 to 1.8 RM, we only reduced the days to maturity by 5 days. If planting is delayed past June 15, you may want to consider changing your variety to one with a relative maturity that is 0.5 less, so changing from a 3.0 to a 2.5 relative maturity soybean.
Second, regional studies continue to show that narrow row soybeans yield 3-4 bushels/acre higher. If your operation does not own a narrow row planter or drill, you may consider looking for someone to custom plant some acres for you. We are losing about 5/8 of a bushels per acre per day and having an extra planter with narrow rows could help you finish a week early given the recent rainfall patterns. This equates to picking up an extra 7-8 bushels per acre in added yield between narrow row spacing and an earlier planting date, well worth a custom planting rate of $20/acre.
Lastly, your seeding rate may already be high enough to achieve a final stand of 100,000 to 125,000 plants per acre. So no changes may be needed. In the case with some drills, seed spacing can be a problem and you may want to increase your seeding rate on drilled soybeans to hasten canopy cover.
In summary:
- Don’t switch to earlier maturing varieties until after June 15
- Plant narrow row soybean, on average they yield 3-4 bu/ac more
- Don’t lose 5/8 of a bushel per acre per day by delaying planting, get some help with a custom planter
- Depending on your current seeding rate, you may not need to change it
For more information on delayed soybean planting practices, call me at 727-2775 or visit our local website at croptechcafe.org. Know your crop, know your tech, know your bottom line. This is Dr. Nathan Mueller, your local agronomist for Nebraska Extension on KTIC radio..
More Resources:
CropWatch Article on Strategies for Delayed Soybean Planting
