You probably don’t plant when your soil is 77 degrees, and probably not even 57 degrees. How does your seed germinate when the soil temp is 45 or 50 degrees? Hopefully, that’s what a cold germination score can tell you. Also, when seed is scored for either a warm germ or cold germ at a lab, germination alone isn’t enough to pass. If a seed germinates, yet the initial root or shoot is abnormal, that seed is considered a failure. A seed must germinate and grow well initially in order to pass the test.
Unfortunately, no seed company we know of puts a cold germination score on the tag. Also, some of the cold tests are not super accurate. For example, seed labs have told us the saturated cold germ test is not easily repeatable, meaning you could run the exact same sample 5 times and get different results all 5 times.
Here at Hefty’s, we’ve had our own seed lab for years. Moving forward, we’re adding more equipment and people, and we’ll be working on a couple of the newer cold germination tests that are hopefully repeatable and reliable. Until then, we’ll continue to run a standard cold germination test at other labs on all our seed. As a general rule, all our regular corn seed must have a 95% warm germination score and a 90% cold germination score, but most of our seed does hit 95% or better even on the cold germ. With soybeans, the standard has always been 90% warm and 80% cold.
One of the big things that can help a cold germination score (and a warm germ test, too) is the seed treatment. When I personally used to work in the seed lab years ago, I could really see the difference a seed treatment would make. This is one of the reasons why Hefty Brand Corn comes standard with more than 30 seed treatments. It’s also why we encourage you to run a cold germination test on any competitive seed numbers versus any Hefty Brand numbers. We’ve had farmers doing this for the last couple of years, and it has led to a lot of farmers switching over to Hefty Corn. Our cold germination scores, on average, have been higher than any other brand that we and other farmers have tested.