DIGGING INTO THE POTENTIAL OF SWEET POTATO PRODUCTION IN THE TRI-COUNTY AGRICULTURAL AREA OF NORTHEAST FLORIDA

Situation: Crop diversification is vital to the sustainability of food systems. The Tri-County Agricultural Area (St. Johns, Putnam, Flagler) of Florida leads the state in production of potatoes (Solanum tuberosum L.), with Hastings being the official “Potato Capital” since 1908. However, in recent years potato growers have been operating on low profit margins, and production acreage is declining. In response, growers are looking for alternatives such as sweet potato (Ipomoea batatas L. Lam.) to diversify their farming systems and enhance sustainability. Information about sweet potato production in the area is lacking, and growers are relying on UF/IFAS Extension to help get the information needed. Methods: Field trials were conducted at the Hastings Agricultural Extension Center from May to September 2016 to evaluate yield, identify the optimal nitrogen (N) rate, and compare row spacing on selected cultivars. ‘Boniato,’ ‘Burgundy,’ ‘Covington,’ and ‘Palmetto’ were planted using two row spacings (40” and 80”) and four N rates (lbs/A) (0, 60, 90, 120). Results: Yields were significantly different for the four tested cultivars. ‘Boniato’ was the greatest yielding followed by ‘Burgundy,’ ‘Palmetto,’ and ‘Covington.’ The 90N rate resulted in the greatest yields for all cultivars. Due to insufficient slips, only the 40” row spacing was evaluated. Conclusions: Although ‘Boniato’ and ‘Burgundy’ had greater yields, ‘Palmetto’ may demand a better price with a promising market potential for Florida because of its high content of purple anthocyanin, an antioxidant that not only makes this sweet potato a superfood, but gives it an alluring purple color. Among the nitrogen rates, 90N had the best yield and nitrogen use efficiency. Thus, 90N may be considered as an appropriate nitrogen application rate for sweet potato production in the area.