Sweetpotato Storage Root Yield As a Function of Plant Age

Sweetpotato, Ipomoea batatas L.(Lam.) is commercially propagated by stem cuttings from shallow storage root beds. Once cut, new plants arise from nodes of residual stems in the bed and allow for multiple cuttings in a season. The plants arising from the storage roots continue to grow at the apex and growers routinely clip the top growth by mowing so uniform sized plants are maintained for transplanting. Plants are normally cut when reaching 25 cm, but rain may delay transplanting by weeks and beds are topped multiple times. Growers express concern that older transplants may perform poorly in comparison to new growth transplants. ‘Orleans’ variety transplants of varying type and age (new growth, second cuttings, and plants topped over 4 weeks) were compared to determine if transplant age effects storage root yield and quality by grade. Results showed no statistical difference between older transplants and new growth transplants for three grades of sweetpotato and total marketable yield.