Super Sweet sweet corn varieties

Last time around, we took a close look at the various types of sweet corn available to home gardeners and commercial corn producers. We cited the Standard (Su) hybrid type, which include the old standby varieties, Silver Queen and Golden Queen. Next were the sugary enhanced (Se) varieties with higher sugar content such as Ambrosia and Silver King. We noted that Sh2-Shrunken (Super Sweet) varieties have even higher sugar levels and hold their peak sugar levels longer than both Su and Se varieties. Synergistic (Sy) varieties combine the tenderness and flavor of the Se genotype and the sweetness and holding ability of the Sh2 genotype. Lastly, the Improved Super Sweets boast of a perfect blend of tender Se type kernels and the higher sugar content of the Sh2 kernels plus excellent holding ability.

Since the discovery of the Sh2 gene and the development of the first Super Sweet sweet corn varieties in the 1960s, remarkable strides have been made in refining their stand-out features-high sugar content and slow conversion to starch.

Most recently, breeding efforts have further refined Super Sweets, giving them a suite of quality and cultural traits, including strong seedling vigor, disease resistance, and greater field holding capacity, along with the previously discussed superior sweetness, tenderness, and flavor.

Although great strides in seedling vigor have been made, Super Sweets and Improved Super Sweets are more sensitive to cold soil than their Standard Sugary, Sugary Enhanced, and Synergistic counterparts. These should be planted in soils with temperatures of at least 60 degrees.

Today’s seed catalogs contain scores of sweet corn varieties-so many that one can become confused about which varieties to grow. Knowing the genetic type of each hybrid is essential as the grower prepares his cropping plan. Each genetic type carries some risk of cross-pollination with other types, which can negatively impact eating quality in the crop produced. Maintaining isolation between types or selecting hybrids within compatible genetic types will ensure that the eating quality of each hybrid will be preserved.

A knowledge of isolation is critical. For all sweet corn varieties, isolation is necessary to protect the high sugar and flavor characteristics of the sweet corn, as cross-pollination from other types of sweet corn or other types of corn, such as field corn or popcorn, will result in starchy kernels.

Se/Synergistic types and Sh2/Improved Super Sweet types should always be isolated both from each other and from the other types of corn as noted above. Standard (Su) sweet corn should be isolated from field corn, popcorn, and Sh2 varieties.

Isolation can be achieved either by distance, a difference in maturity, or by planting at different times. Preferable isolations would require a 700-1000 feet distance from other corns or 10-14 days between pollination.

Another sweet corn that has recently come upon the scene is SuperSeedWare (SSW). SSW is a new and exciting breakthrough in Super Sweet corn genetics. Developed and patented by Abbott and Cobb, SSWs are 100% (non GMO). They have notably enhanced performance even with early plantings in colder or wetter soils. Growers can expect stronger stalks and root systems, early maturity, better disease tolerance, and high yields. SSW varieties also exhibit dramatically improved seed storage and shelf life. As with other sweet corns, isolation from other types of corn is essential to ensure the best possible eating quality and plant traits.

I hope you have enjoyed this look at sweet corn and you will grow the finest sweet corn ever this year.

Tim Lewis is a Georgia Green Industry Association Certified Plant Professional, gardening writer, former Perry High School horticulture instructor, and former horticulturalist at Henderson Village and Houston Springs. He and his wife, Susan, own and operate Lewis Farms Nursery located on Hwy 26 two miles east of Elko, where he was born and raised. He can be reached at (478)954-1507, timlewis1@windstream.net, or at LewisFarmsNursery.com.

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