Phosphorous and Potassium Fertilizers Influence Establishment of Bermudagrass

Grady Miller*, University of Florida; Bert McCarty, and Ian Rodriguez, Clemson University.

Establishment of an acceptable turfgrass quality on sand-based golf putting greens presents major agronomic and environmental challenges to turfgrass managers. The objective of this study was to evaluate five N:P:K fertilizer ratios to aid in the establishment of bermudagrass on sand-peat (85:15 v/v). ‘Floradwarf’ and ‘Tifdwarf’ bermudagrass [Cynodon dactylon (L.) Pers. X C. transvaalensis Burt-Davy] were sprigged in August 1996 at the Envirogreen in Gainesville, FL. ‘Tifeagle’ and ‘Tifway’ bermudagrass were sprigged in May 1999 at Clemson University research green in Clemson, SC. Treatments consisted of N:P2O5:K2O ratios of 1:0:1, 1:0:2, 1:1:1, 1:2:1, and 1:3:1 applied based on an N rate of 49 kg ha-1 wk-1. Treatments were applied weekly for seven weeks. In Gainesville, the best growth rate was achieved from the 1:1:1 ratio of N:P2O5:K2O. While the 1:2:1 and 1:3:1 plots filled in well, they did not experience the same coverage rates as plots fertilized with the 1:1:1 ratio. In Clemson, similar growth was achieved with the 1:1:1, 1:2:1, and 1:3:1 treatments. The 1:0:1 and 1:0:2 plots were slow to establish at both locations. In general there were no differences in root and shoot dry weights of grasses grown in Clemson; whereas, these weights were positively correlated to growth rates in Gainesville. These studies indicate that turf will respond to P fertilizer when it is grown in a P deficit situation and that N or K cannot substitute for balanced nutrition.