Fertilizer Rates when Costs are High (Part 2 - starter fertilizers) (04/28/22)
Phosphate fertilizer placed with or near the seed are important for the following crops to more consistently reach their environment-directed yield potential:
Corn
All small grains
Canola
Sugar beet
Potato
Soybean should not have any fertilizer, except for iron (Fe) in iron-deficiency-chlorosis (IDC) prone areas in eastern ND with water as a carrier. Consistent yield decreases and never a yield increase resulted from seed-placed fertilizers at Carrington over a number of years with a number of products.
Sunflower and flax yield is not increased with P application, so no P is recommended for sunflower and flax regardless of soil test P value and whether it is broadcast or banded.
In dry bean, small yield gains have been seen in Carrington research with low starter P rates (2 gallon per acre, but not more), except in 2021 in very dry soils when yield decreases were noted. Starter is not necessary, but it may be helpful.
Present yield results from starter placement with pulse seed is not compelling, but it might be more logistically practical compared to broadcast and I have not read anywhere where it was detrimental to yield. More research is necessary to better indicate pulse response to starters in a range of soil test P soils.
Extension Soil Specialist, 701-799-2565
