| Experiments were conducted to evaluate and improve methods for landscape fertilization of bedding plants.; Experiments 1, 2, 3, and 4. Fertilizer treatments, evaluated during the summers and winters of 1998 and 1999, were applied to landscape bedding plants in raised beds simulating an urban landscape. Fertilizers evaluated included: Osmocote 14-14-14 and 17-7-12 controlled release fertilizers (CRFs), 13-13-13 and 15-0-15 granular water-soluble (GWS), an industry practice treatment (IP) of incorporating a CRF preplant and topdressing a GWS fertilizer postplant, and an organically-based fertilizer (OBF) composed of recycled newspaper and chicken manure. Methods of fertilizer application evaluated included: topdressing fertilizers preplant or incorporating postplant, and applying fertilizers in a single application preplant or in multiple applications throughout the growing season. Data collected included foliar color ratings, growth index, foliar nitrogen (% of dry weight), shoot dry weight, and inorganic N recovered in soil solution from suction-cup lysimeters. Fertilizers applied in multiple applications improved plant foliar color, foliar N, and growth index, and did not increase total-N recovered in soil-water. CRFs generally improved foliar color and plant size compared to GWS fertilizers, while reducing total-N in soil water in some instances. The IP treatment generally provided superior foliar color and larger plants compared to other inorganically fertilized plants, though in some experiments it caused higher levels of total-N recovered in soil-water. The OBF generally resulted in larger, more attractive (higher foliar color ratings) plants than those fertilized with inorganic fertilizers.; Experiments 5 and 6. Two experiments were conducted to determine the relationship between foliar nitrogen (% of dry weight) (FN) in pansy (Viola x wittrockiana ‘Bingo Yellow’) and either sap nitrate concentration (SN) in pansy petioles or SPAD-502 chlorophyll meter readings of pansy foliage.; Experiments 7, 8, and 9. Three experiments were conducted to develop a method for rapid determination of nitrogen (N) status in vinca (Catharanthus roseus (L.) G. Don ‘Pacifica White’). (Abstract shortened by UMI.)... |
