Attempts to use dent corn (Zea mays L.) to improve sugary‐1 (su) sweet corn have not been widely successful due to difficulty with the simultaneous recovery of traits being transferred and acceptable quality. The lack of success may be caused by linkage, pleiotropy of the su gene, inadequate recombination before initiating selection, or insufficient population size. The objective of this study was determine if the su allele affects 19 important sweet corn traits. Plants from starchy (Su) and sugary (su) So seed of a dent ✕ sugary composite were grown in four environments at 36 900, 57 400, and 73 800 plants ha−1, with ear measurements recorded at milk‐stage maturity. The Su and su S1 progenies were grown in two environments at 51 700 plants ha−1, with data taken on mature dried ears. Sugary So segregates demonstrated a greater tendency toward delayed maturity and lodging than Su segregates. Tip blanking was reduced in su So and S1 plants. Ear length was reduced in su So plants and Susu plants from Su‐‐S1 ears. Plant endosperm type had no effect on percent marketable ears or yield among So segregates, or on S1 ear diameter, taper, and curvature. The su gene effects provide some explanation for the difficulty encountered when using dent corn in sweet corn improvement, but were not so pronounced as to be insurmountable in a breeding program.