Early Planted Soybeans: The Risks & Rewards

Stuart Carlson, Northern Product Agronomist
April 12, 2021

Planting soybeans early has a different meaning than it did 30 years ago.  During my first job as an agronomist, I was told that “a soybean plant should not see the light of May”.  Boy that sure has changed with the pictures on twitter of guys planting soybeans in Iowa in March.  I am not promoting planting soybeans that early, BUT what has changed to give farmers the confidence in planting earlier than ever before?

Even though many of us have just started to dabble in planting a little earlier, land grant Universities have been working on this for several years now.  Universities such as ISU and UNL studies show that a planting date for high yielding soybeans is around May 1st.

The REWARD

The two big rewards are potential yield advantage and spread out the spring work load.  The plant will try to accomplish these benefits in several different ways.

  • Plant canopy – With earlier planting, the soybean plant should produce a larger canopy earlier in the season.  Earlier canopy will shade the ground quicker and capture more solar radiation which leads to higher rates of photosynthesis.
  • Longer growing season – The longer growing season usually equates into a longer reproductive stages which has the potential of increasing the number of nodes.  More nodes in favorable weather will have more flowers, pods which leads to more seeds.

The RISK

The single highest risk that most farmers are worried about is frost. Growers also need to manage insects, disease and stand establishment.  It is vital to protect your seed as much as possible with Hoegemeyer's LumiGEN® seed treatments.

  • Early season insects – Bean Leaf Beatle is one of the biggest risks in early planted soybeans because they overwinter.  If the soils are cool, root development is slower for BLB feeding and for feeding on newly emerged plants.
  • Early season diseases – Soil diseases are particularly tough on seedlings in cool soils.  Good high-quality treatments such as LumiGEN® seed treatments for Hoegemeyer brand soybeans will help protect against seedling pathogens; Phytophthora, Pythium, Rhizoctonia and Fussarium.  SDS is a disease that has a higher rate of incidence when cool saturated associated with early spring planting.  ILEVO® is a very viable seed treatment option to help you protect against SDS.
  • Stand establishment – I believe this is the most important part that needs to be managed is planting early.  LumiGEN® seed treatment is a premium treatment and is a must in planting soybeans any time of the year.

Planting soybeans early can reward you with varying degrees of yield advantage, spreading out workloads and conservation of moisture.  BUT it also has some risk and those risks need to be managed to produce a greater chance of a positive outcome.

Be sure to contact your local Hoegemeyer representative with any questions!