Early Planting: A Few Short Days Away

Six factors farmers need to know about early planting  

Soybeans have the largest planting window of any crop grown in Mississippi. Thanks to the benefits it provides farmers, including higher yields and easier pest management, planting early (late March through mid April) has become the common practice in the Midsouth. Mississippi Soybean Promotion Board’s research and technology transfer coordinator Larry Heatherly, Ph.D., provided much of the scientific basis for the current trend to earlier planting in the Midsouth.  He says switching to earlier planting accounts for a lot of the Midsouth’s soybean yield improvement over the past 15 years. Last year, Mississippi soybean yields averaged 46 bushels/acre. Compare that with 2000, when the state averaged 22 bushels/acre. 

Here, he outlines six factors to consider when determining planting date:

  1. Maturity Group –Soybean varieties grown in the Midsouth generally need 135 to 140 days from planting to maturity to reach full yield potential. Group 4 varieties planted early fit this criterion. Group 5 varieties can also be planted early, but their longer growing season provides no yield advantage and likely will require more late-season management. Heatherly, a retired U.S. Department of Agriculture-Agricultural Research Service agronomist emeritus at Stoneville, stressed that using proper at-planting management – mainly the proper fungicide seed treatments – is key to producing high yields with early plantings. 
  2. Insect Management – Early planting also helps avoid late-season foliage-feeding insect infestations. MSPB-funded research suggests that most insect pressure can be eliminated by planting early. 
  3. Irrigation Management – Heatherly also says using soil-moisture sensors for irrigation initiation and termination, and not starting irrigation too early, will allow farmers to save at least one irrigation, thereby conserving water. 
  4. Reduced Tillage – With much of Mississippi soybean acres planted on clay soils, there’s the likelihood that harvest of later-planted, late-maturing varieties may occur when these soils are wet.  But planting early allows farmers to harvest soybeans when clay soils are at their driest, ensuring farmers can have limited to no tillage for the following crop. 
  5. Disease Management –Early planting also helps avoid some diseases. For example, early-planted soybeans develop before rust can set in. However, rainy weather may delay planting until conditions are more favorable for development of these diseases, so farmers should be cautious and not depend on early planting alone to control diseases.  
  6. Weather Conditions – The greatest risk with early planting is cool air after emergence. For early planting, it’s important to know the estimated date of the last spring frost, or if low temperatures that will result in a frost or freeze are still expected to occur after emergence.  Mississippi farmers can find the estimated dates for most locations here, so they are better able to find an early planting date that suits their operation.