Corn Germination

Farming is more than planting a field and hoping it all works out. We keep a close eye on our crops throughout the growing season  and then evaluate the harvest when it’s all said and done. This last year, our 150-foot plot of sweet corn didn’t do as well as it had in previous years and we want to know why so we can try to prevent such a low yield in the future.

 And this is when the farmer takes on a more detective role. We consider things like the weather of the previous season: was it too cold or warm, too wet or dry? We look at when the seed was planted. Were we late and the seed didn’t have the time it needed to grow? Were we too early and the ground too cold? There’s always the possibility of wildlife , be it rabbits, deer or insects destroying the crop . But we also consider the seed itself.

 In the case of our sweet corn, a good portion of what we planted just didn’t sprout. And the best way to figure out why is to conduct a simple germination, or sprout, test. This is the sort of experiment you may have done in grade school, setting out a handful of seeds on a plate and a wet paper towel and covering everything with plastic wrap to keep the moisture in. Basically what we’re doing is inducing germination to determine if the seeds we planted last year were bad. But last year we planted more than one kind of sweet corn seed.

 In 2013, we purchased and planted a sweet corn seed that produced a good yield when it came time to harvest. But seed can be expensive and we wanted to see if we could use the seed from our crop to plant the next year and still retain the same quality while starting to develop on open pollinated stable variety out of this hybred. So in 2014, we split the plot and planted the leftover purchased seed on one half and the seed from our harvest on the other. Neither did very well which is why today we’re testing three kinds of seeds.

 The first group of seeds are the original seeds purchased in 2013. The second group of seeds are the result of our 2013 crop. These seeds were pulled from the cob and stored through the winter at room temperature. The third and final group of seeds are also the result of our 2013 crop, but these seeds were kept on the cob and stored at a cooler temperature.

 For each group we counted out 100 seeds and did exactly what you did in grade school. Left at room temperature, the seeds will sprout much faster than they do in the cool, Montana earth, but timing isn’t what we’re looking at. What we want to know is how many seeds actually sprout and a few days later we have our answer.

 In our first group of seeds, we had 93% germination. Or in other words, 93 of our 100 seeds had sprouted or were showing signs of growth. Since seed markets require only 75% germination, this is well above the limit. Our second group of seeds, on the other hand, had only 79% germination. While this is still above the limit, it’s quite a bit lower than the original seed, which may be all the answer we need. But even more interesting were the results of our third group of seeds. In this group we had 91% germination, which suggests that perhaps storing the seed on the cob or at cooler temperatures is beneficial for planting the following season.  Or we could have taken the seed off the cob before it had matured completely lowing the germination.  

 Overall the germination results indicate that the lack of sprouting in this last year’s crop was probably not due to bad seed. The most probable cause was that the earth was too cool when we planted and the seeds which are in organic production and not treated with fungacides rotted  before they could grow.

 For 2015, we will likely plant the purchased seed on the majority of the plot and dedicate the rest for the seed that was stored on the cob. With a lot of work and a little luck, we should have a better harvest of sweet corn this fall.