Soybean Production in Mississippi
What are the recommended planting dates for soybeans?
Planting dates vary because soybeans have the largest planting window of any crop grown in Mississippi. The maturity group, or variety being planted, plays a large role in planting-date decisions.
Planting dates can be placed into two categories: optimum and acceptable. The optimum time frame is when the fastest, most uniform emergence would occur. Acceptable dates are much broader, and planting can range from mid-March to mid-July and be successful. Even though soybeans are photo-period sensitive, the maturity of a variety is not shifted forward nearly as much due to early planting as if planted late. To spread your risks, vary maturity groups rather than spacing out planting dates.
Early season soybean production has increased in acreage over the last several years because of grower success. The interest in early planting of earlier maturing varieties has really changed the picture regarding soybean production. Earlier maturing varieties commonly referred to as Group IVs have allowed growers to increase yields by avoiding late summer weather patterns that are typically hot and dry.
Even though early maturing varieties have increased in popularity, they are not the only option. Using early plantings of maturity Group Vs can increase yield levels as well. Planting date recommendations are used to encourage later plantings, but new genetics, the temperature requirements for germination, and the potential increase in yields from earlier plantings have shown a need to change from what growers once practiced. A real opportunity exists to plant soybeans earlier than traditionally, given the crop's ability to handle weather extremes (cool weather). Growers need to plant a portion of the soybean crop before cotton. For many growers this could mean planting an entire soybean crop early.
Planting earlier than mid-April is more risky, but many have had success planting late March to April. In the future, you may move planting dates even earlier if varieties are developed that will provide sufficient vegetative growth under adverse early conditions. A lot of interest has been expressed regarding planting full season varieties early. Although planting date information at this time is not complete, Group V varieties are looking good. Tests have been implemented that should answer this question, and it appears many of the new varieties are not as photo-period sensitive as older varieties; therefore, early planting later maturity groups (Group Vs) would be a good option. Just taking advantage of timely planting, not necessarily Group IVs, can contribute to increased yields.
Late planting dates are usually the most damaging to yields. Yield losses are quite variable, but after mid-July, yields decline rapidly.
Because of weather, large acreage, limited equipment, and other management considerations, it may not be possible to plant your entire acreage in the ideal time frame (April 20 to May 10). In general, yields will be positively affected by planting earlier than this period versus the negative effect on yield from planting later. If there is a likelihood you cannot plant the entire crop during the optimum time, it is better to begin planting early rather than risk late planting.