Natural organic fertilizers require microbial degradation for nitrogen (N) release, but their ability to promote rapid turfgrass establishment has not been well documented in newly constructed sand-based rootzones. This 2-year field study evaluated the influence of two general fertilizer and soil amendment programs for their effect on establishment and quality of three creeping bentgrass (Agrostis stolonifera L.) cultivars—`Crenshaw', `Penn G-2', and `Providence'. Turf was grown on a 4 sand: 1 sphagnum peat (by volume) rootzone mixture. Four treatments consisting of surface-applied synthetic fertilizer (SF; mostly water-soluble N in 1999 and methylene urea thereafter); surface-applied hydrolyzed poultry meal (PM); preplant-incorporated granular humate (GH) with surface-applied SF; and preplant-incorporated PM with surface-applied PM. Turf cover data collected 42 days after seeding (DAS) showed that the rate of establishment was SF+GH incorporated = SF surface-applied >PM surface-applied + PM incorporated >PM surface-applied. Turf cover was ≥96% among all treatments 90 DAS. Rootmass density was greater (18% to 29%) at 103 DAS in GH incorporated plots combined with SF, when compared to all other treatments, but no rootmass differences subsequently were observed. Soil microbial activity generally was highest in PM-treated plots during the first 14 months following seeding, but not thereafter. Turf treated with SF had less microdochium patch (Microdochium nivale (Fr.) Samuels and I.C. Hallett) and more bentgrass dead spot (Ophiosphaerella agrostis Dernoeden, M.P.S. Camara, N.R. O'Neill, van Berkum et M.E. Palm), when compared to PM-treated plots. Slightly less thatch developed in PM-treated turf when compared to plots receiving SF alone by the end of the second year. Penn G-2 and SF generally provided the best overall turf quality. This study demonstrated the beneficial effects of readily available N from SF for rapid establishment and that preplant incorporation of GH initially aided root development.
COMPARISON OF THE EFFECTS OF ORGANIC FERTILIZERS WITH INORGANIC FERTILIZERS ON THE GROWTH OF EIGHT MONTHS OLD COCONUT SEEDLINGS AND THE NUTRIENT AVAILABILITY AND SOIL MICROBIAL ACTIVITY OF SOILS
