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In Florida, multiple counties restrict the application of N to turfgrass and landscapes during the summer rainy season. These summer fertilizer blackout periods could impact turfgrass quality and the functionality of warm‐season turfgrass species. A 2‐year study was conducted at the University of Florida's Fort Lauderdale Research and Education Center (FLREC) and West Florida Research and Education Center (WFREC) to assess turfgrass performance of 'Floratam' and 'Classic' St. Augustinegrass [Stenotaphrum secundatum (Walter) Kuntze] as well as 'Empire' and 'Palisades' zoysiagrass (Zoysia japonica Steud.), respectively, receiving no N fertilization during summer blackout period using eight fertilization programs compared to an unfertilized control. Visual quality, normalized difference vegetation index, percentage green cover, and dark green color index were assessed biweekly. Roots were collected before and after the fertilizer blackout period to determine root dry weight. While no differences were detected in St. Augustinegrass at the FLREC and zoysiagrass at the WFREC, all fertilized treatments except urea reached and maintained an acceptable turfgrass quality (≥6) throughout the blackout period, suggesting that urea by itself was not sufficient to support an optimal turfgrass performance during a fertilizer blackout period. The addition of P to nutrition programs did not influence turfgrass quality. Results indicate that N source is the most important factor to sustain turfgrass quality year‐round in Florida. Plain Language Summary: Fertilizer "blackout periods" are periods where it is prohibited to apply fertilizer, instituted to prevent the leaching of plant nutrients into water bodies. However, their effect on turfgrass health has not been extensively studied. In our research, we investigated eight different fertilizer programs that were applied outside the summer blackout fertilizer period. Results indicate that N fertilization during the spring is essential to maintain turfgrass health when summer fertilizer blackout periods are enforced. However, older turfgrass stands could sustain turfgrass quality with limited to no N applications year‐round. [ABSTRACT FROM AUTHOR]

Several new bermudagrass cultivars are available and commonly used on golf course fairways. However, little is known about their cultural requirements or how these cultivars perform under lower inputs regimes. A 2‐year study was conducted at University of Florida, Fort Lauderdale Research and Education Center, to assess performance of four hybrid bermudagrass [Cynodon dactylon L. Pers. X Cynodon transvaalensis (Burtt‐Davy)] cultivars ('Latitude 36', 'Tifway 419', 'TifGrand' and 'TifTuf'), and 2 common bermudagrass (Cynodon dactylon L. Pers.) cultivars ('Bimini' and 'Celebration') irrigated at either 50% or 80% reference evapotranspiration (ETo) and fertilised at either 0, 146, 244, or 342 kg N ha−1 year−1. Plots were evaluated monthly for turfgrass quality, dark green colour index (DGCI), normalised difference vegetation index (NDVI), and Chlorophyll Index, and seasonally for N tissue content. Plots watered at 80% ETo enhanced bermudagrass quality compared to 50% ETo, DGCI and NDVI only in two months out of 24. Latitude 36 and Celebration were the top‐rated cultivars, and their quality was not affected by no N fertilisation. Conversely, TifGrand, TifTuf and Tifway that received no N fertilisation resulted in insufficient quality during the second year of the study. Insufficient quality may be linked to reduced N metabolization compared to the highest rated cultivars. Results show that new cultivars such as Latitude 36 and Bimini could be maintained at sufficient quality levels with reduced water and N inputs in South Florida. [ABSTRACT FROM AUTHOR]

The article presents a study which examines turf response and nitrate (N) (NO3-N) leaching to irrigation regime and nitrogen rate (NR) in Empire zoysiagrass (Zoysia japonica) and Floratam St. Augustiengrass (Stenotaphrum secundatum) in Citra, Florida from 2005-2007. Irrigation treatments comprised of 2.6 centimeter (cm) applied once weekly or 1.3 cm applied twice weekly. Turf quality (TQ) was above an acceptable level in St. Augustinegrass at all NRs in zoysiagrass and at all but the lowest NRs with the exception of the spring fertilizer cycle (SFC).