Calcium chloride at 1% was sprayed on the foliage of potted soybean plants of the Santa Rosa cultivar as a single application at 20, 40 or 60 days after germination or combined as two or three applications at the same dates. A single spray at 40 or 60 days after germination (10 days prior to or 10 days after full blooming) gave the best response. The number of pods per plant was increased by 16-20% and the soybean yield was increased by about 10%.