In addition to its seed-coat fibers, cotton produces bast fibers comparable to those of hemp and kenaf. The aim of this study is to modify cotton’s bast fiber properties by altering cell wall chemistry, and to survey natural bast fiber diversity found in Gossypiyum spp. germplasm. Modification of cell wall chemistry is achieved through Virus-Induced Gene Silencing (VIGS) of genes along the lignin biosynthesis pathway. Natural bast diversity is assessed from a panel of 23 distinct cotton cultivars. Whole-stem cross sections are analyzed by UV microscopy, and bast fiber constituents are analyzed by acid-hydrolysis prior to High Performance Liquid Chromatography (HPLC) compositional analysis. We show Deltapine 14 and Tidewater 29 to be the two most productive cultivars in terms of bast mass. We also find differences in the carbohydrate profiles of retted vs. unretted bast fiber samples from various sources.