Effect of iron fertilization on the growth of bermudagrass and zoysiagrass under shade and full sun

Field research was conducted in 2017 and repeated in 2018 to investigate the responses of two warm‐season turfgrasses, Diamond zoysiagrass [ Zoysia matrella (L.) Merr] and Tifgrand bermudagrass ( Cynodon transvaalensis Burt‐Davy x C. dactylon ), to four levels of foliar applied ferrous sulfate (FeSO 4 • H 2 O), control, 1, 3, and 5 kg ha −1 Fe grown under full sun and 40% continuous shade in the southern transition zone. The research was divided into four independent studies due to geographical differences in location: Diamond zoysiagrass under shade, Tifgrand bermudagrass under shade, Diamond zoysiagrass under full sun, and Tifgrand bermudagrass under full sun. Each study was assessed based on visual turfgrass quality (TQ), Normalized Difference vegetative index (NDVI), shoot chlorophyll index, shoot tissue nutrient concentrations, total root and verdure biomass, and verdure bulk density. TQ was highest with iron application to Tifgrand bermudagrass under full‐sun conditions. However, increases in TQ from iron applications were short‐lived. Overall, iron fertilization appears to enhance turf color and quality when grown in full sun to moderate shade. Foliar Fe fertilization was observed to have the greatest impact on turfgrass quality (TQ). Color enhancement after foliar applications of Fe was short‐lived on vigorously turf. Fe fertilization periodically enhanced both the color and quality.