Studies on Prebloom Sprays of Gibberellin to Elongate and Loosen Clusters of Thompson Seedless Grapes

Prebloom sprays of gibberellin applied to Thompson Seedless vines failed to elongate the clusters sufficiently to result in loose clusters on vines that were later girdled, sprayed with gibberellin at shatter, or both. A preliminary experiment showed a wet-table powder containing potassium gibberellate, and an ether gibberellate were both effective in increasing berry size of Thompson Seedless grapes.