Influence of Three Nitrogen Fertilization Schedules on Bermudagrass and Seashore Paspalum: I. Spring Green‐up and Fall Color Retention

Abstract

ABSTRACTA primary concern in managing warm‐season turfgrasses within the transition zone is the lengthy dormant period, during which these swards lack green color. The objectives of this study were to determine the effects of three N fertilization schedules on spring green‐up and fall color retention of bermudagrass [Cynodon dactylon (L.) Pers.] and seashore paspalum (Paspalum vaginatum Sw.). A field trial was performed at the agricultural experimental farm of Padova University (northeastern Italy). Bermudagrass cultivars Princess‐77, Riviera, SWI 1014, and Yukon and seashore paspalum ‘Sea Spray’ were compared under three N fertilization schedules: (i) 6.7 g N m−2 on 15 May, 15 June, and 15 August, (ii) 5 g N m−2 on 15 May, 15 June, 15 August, and 15 October, and (iii) 4 g N m−2 on 15 May, 15 June, 15 August, 15 September, and 15 October. Spring green‐up was estimated weekly as a percent green turfgrass coverage from 15 March to 15 June of 2010 and 2011. Fall color retention was visually rated from September to November of 2010 and 2011. Sea Spray seashore paspalum had later spring green‐up and better fall color than the bermudagrass cultivars, which differed widely in terms of spring green‐up and fall color retention. Fall‐applied N enhanced green‐up of all the grasses tested and extended fall color retention of bermudagrass cultivars. This study revealed that protracting applications of N fertilizer until late season may improve quality performance of warm‐season grasses without increasing annual N applied.