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Planting started very early in our area, and with the dry spring we’ve experienced planting has progressed at a near record pace. I have personally talked to more than one soybean grower who told me this is the first year they have ever planted soybeans in April. The dry spring gave us the opportunity in Northwestern Illinois to plant soybeans early. I’m glad more soybean producers are realizing waiting till May to start planting soybeans is not necessary and can reduce your yield potential.

There are always exceptions and limits and anything can be taken too far but, generally speaking, when you have ideal to dry soil conditions, low soil temperatures alone are not enough to cause a problem for soybeans. There are also tradeoffs that have to be made when planting. If you don’t want to finish “late” then by necessity you have to start “early,” because most of us can’t plant our entire corn and soybean crops in a week. While it can seem risky to plant early, the success of those who routinely plant early shows us risks are manageable and failures are uncommon.

Logistics also become a big challenge. Can you plant corn and soybeans at the same time or do you use the same planter for both? Does your operation have the equipment and manpower necessary to support planting corn and soybeans at the same time? In recent years planting date studies from industry and universities have shown the highest soybean yields often come from soybeans planted between April 20th and May 5th, very similar to the optimal window for corn.

If you have not finished planting soybeans yet you may be wondering if I am saying you can’t still raise good soybeans. Luckily, that is not what I am saying. Most years we can still get good yields from soybeans planted in May. In some years even planting into June can still produce good yields as well. But if you are trying to win a yield contest or set a new personal best for soybean yields that is less likely to occur as we move into May.

Early planted soybeans canopy sooner and produce more main stem nodes, which contributes to their greater yield potential. The data also suggest that early planted soybeans tend to respond better to other high yield management practices, such as additional fertility and fungicide applications. It’s still true that late summer weather is a bigger yield determining factor for soybeans than planting date. Planting date, variety selection, row spacing, weed management, fertility, diseases and insects all affect yield potential. However, we need a healthy plant and favorable weather conditions mid to late summer to realize the greater yield potential offered by early planting.

Planting soybeans early is a good strategy. This year weather cooperated, but in some years it won’t. Don’t fret too much if it seems to get late some springs, the window for planting and still reaching optimal yield extends to about May 10.

Lance Tarochione is a technical agronomist with Asgrow/DEKALB in west central Illinois. His work has focused on crop production, research and product development, and through his role at Monsanto^® he currently supports the Asgrow^® and DEKALB^® brands in seven counties in western Illinois.