Sweet Corn Varieties

Sweet corn varieties are categorized by their genotype.  The most common varieties are normal or sugary (su), sugar enhanced (se), and supersweet or shrunken types (sh2).  Other newer varieties include sweet breeds, synergistic, sweet genes, or improved supersweets which have a combination of genes.

su           "Normal or Sugary"

Standard hybrid sweet corn is a mutant type of corn that differs from field or dent corn by a mutation at the sugary (se) locus.  The standard hybrid sweet corn accumulate about two times more sugar than field corn.

se           "Sugary Enhanced" or "Modified Sugar" or "Everasting Heritage" (EH)

se +        Homozygous Sugary Enhanced 

These are two distinct groups within the cultivars containing the "se" gene.  Firstly, there are the "Homozygous se" or se+ cultivars.  They have higher sugar levels in 100% of their kernels.  The other group includes cultivars containing the "Heterozygous se" gene.  They have higher sugar levels in 25% of their kernels; the other 75% contain the normal su gene with lower sugar level.  So "Homozygous se" cultivars are usually sweeter than "Heterozygous se" cultivars.

• Sugar conversion to starch is about the same rate as standard sweet corn.  Refrigeration is essential to maintain quality.
• Isolation not required, but desirable.  Note directions on seed tag label.
• Kernels tender and creamy.
• Tip cover weak on some varieties

• Sugar content twice as high as standard sweet corn.
• Slow sugar conversion to starch so quality will hold 7 to 10 days. Refrigeration suggested to extend quality.
• Isolation is required from all other types of corn.  Note direction on label.
• Kernels can be somewhat tough or crunchy.
• Does not germinate well in cold, wet soil.  Plant after soil temperatures exceed 65°F and be sure there is adequate soil moisture.  Adjust planting depth for soil conditions and soil type.  Seed of the sh type is light-weight, wrinkled, and fragile and should be handled gently to prevent damage.

Others

These include synergistic or improved supersweets such as Sweet Breed and Sweet Genes.  Sweet corn breeding programs have developed varieties that have combinations of su, se, se+, or sh2 genes.  Synergistic varieties having the sh2 gene may be grown with other "Super Sweet" varieties, but must be isolated from se and su types to achieve best quality.