Tips for Choosing the Hybrid Maturity

As farmers make their final seed purchasing decisions, some may wonder if the hybrids they selected in early fall are still the right ones today. The Latham Team will gladly help put your mind at ease.

Let’s begin by reviewing a few product selection basics. Most selection decisions begin with relative maturity (RM). These ratings are relative to physiological maturity and largely driven by a combination of growing degree days (GDDs) and planting date. When building a plan for the upcoming growing season, identify the GDD range and average required for a hybrid to reach physiological maturity (black layer) in your geography.

Planting multiple hybrids of varying maturity will reduce risk in three main areas:

  1. Agronomics (emergence, stalk strength, disease tolerance)
  2. Harvest management (harvest moisture)
  3. Genetic diversity (yield, drought tolerance)

About 60 to 70% of a farmer’s portfolio traditionally is focused on the core RM zone (i.e. 100-day RM) with 10 to 20% focused on earlier RM and the remainder on later RM. Remember, there is typically more yield variability within a given RM group. Spreading risk across a wider maturity range is especially important given the moisture limitations across the Upper Midwest.

Grain moisture at harvest also increases steadily with increasing relative maturity. On average, grain moisture at physiological maturity increases by 0.25 to 0.5% with each one-day increase in relative maturity. Selecting hybrids of appropriate maturity is important for a balance between yield potential and managing grain moisture at harvest, which ultimately grows more corn.

The Latham Team is here to help you feel confident about your seed decisions. After harvest each year, we share results from our own research. We hire third-party companies to plant and harvest Latham Elite trials, so our Product Team members can observe products and take notes at a greater number of locations. As a result, we have recently tripled the number of trials conducted on both corn and soybean products in Iowa, Minnesota, Nebraska, Wisconsin, North Dakota and South Dakota!

Once we identify experimental products from the Elite Trials that meet Latham Seeds’ standards AND fulfill our customers’ needs, we release them for sale. Check out multiple years and multiple locations of Latham® performance at

Yield pays. Latham delivers on that promise, just as we have for more than 75 years. Feel free to contact your local Latham Seeds representative or call 877-GO-LATHAM (877) 921-3428.