Two experiments were undertaken in the course of this study. In the first experiment, thirty-two accessions of Cuphea viscosissima Jacq. collected from the central U.S. were analyzed for differences in callus growth and ability to regenerate plantlets. Calli were initiated from immature embryos on a modified Murashige and Skoog medium containing 1 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D) and 1mg/L 6-benzylaminopurine (BA). Calli were incubated in the dark for three weeks. Plantlets were initiated by transferring calli to new medium containing 0.5 mg/L of BA and for root initiation by removing the hormones from the medium. Variability was observed among accessions for callus weight and plantlet regeneration and only the epicotyl was able to form shoots in vitro. There was no correlation between callus weight and shoot initiation, however there was high correlation between the number of calli that produced shoots and the number of shoots produced;A total of 15 donor plant introductions and their 51 callus regenerated plants were used in the second experiment. The R[subscript]1 families from calli induced from immature embryos were evaluated in the field for somaclonal variation at two Iowa locations: Ames and Crawfordsville. Comparisons were made among the parents and their R[subscript]1 families for the following traits: seed yield, 100-seed weight, percent seed germination, plant height, leaf area, percent oil content, and fatty acid composition. Variability was observed for all traits except for total oil content. R[subscript]1 families had significant increases (P ≥ 0.05) over their parents for yield, percent seed germination, leaf area, plant height, lauric acid (C12:0), capric acid (C10:0), and caprylic acid (C8:0). This somaclonal variation is the first reported in Cuphea. Further evaluation is needed to determine the stability of these possible mutants.