Frank L. Abbott of Bellows Falls, Vermont was a pioneer in the creation of hybrids using Rhododendron prinophyllum, molle, calendulaceum, and arborescens. He developed a group of very cold hardy azaleas—to -25°F or lower. While he named several of them, others were sold as seedlings and named by others—see Carlson and Weston hybrids.
An extensive source on Abbott and his hybrids is “Frank Abbott’s Village of Azaleas”, by John and Sally Perkins, Salem, NH, http://rosebayblog.blogspot.com/2009/09/abbott-azaleas.html. Abbott gave plants freely to friends and neighbors in Saxtons River, VT and the Perkins were able to find and photograph many of the Abbott hybrids while touring the vicinity.
John and Sally Perkins have done extensive study of the ploidy of the Abbott hybrids. ‘Margaret Abbott' (prinophyllum (diploid) X calendulaceum (tetraploid)) is a tetraploid. 'Margaret Abbott' is a Tetraploid, http://rosebayblog.blogspot.com/2011/06/margaret-abbott-is-tetraploid.html. 'Margaret Abbott' was named by Frank to honor his wife. Frank was amazed he crossed a pink with a yellow to produce this lone fragrant ruffled white flower with a yellow flare.
Those wishing an introduction to ploidy in azaleas should read Rules of Engagement: Have Pollen - Will Travel by John and Sally Perkins, Salem, NH, http://rosebayblog.blogspot.com/2009/12/rules-of-engagement.html, and also “Exploring the Ploidy” by John and Sally Perkins, https://azaleas.org/wp-content/uploads/azalean/37/12/articles/Exploring_the_Ploidy.pdf
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