On 2Feb. 1996, rooted cuttings of Pelargonium* hortoruml. H. Baileycvs. Tango and Blues were planted in 750-cm3 (14 cm in diameter) pots containing peat moss mixed with shredded tire rubber (2-6.0 mm particle size) at 0%, 20%, 40%, 60%, or 80%. Plants were irrigated by hand, drip, or ebb-and-flood, and were arranged in asplit-plot experimental design. A wetting agent (Aqua Gro 2000 L, Aquatrols Corporation, Cherry Hill, N.J.)was mixed at the rate of 6ml per 3750 ml of water and 120 ml of solution was applied to each plant. Greenhouse studies indicated that geraniums could be grown successfully in media contain ing up to 20% shredded tire rubber by volume when irrigated by hand. Plants grown in media containing more than 20% rubber were observed to be slow growing and chlorotic. Tissue analysis of the plants indicated significantly in creased levels of zinc in plants grown in media containing high percentages of rubber. Geraniums grown in media containing 80% rubber and irrigated using ebb-and-flood benches had the significantly highest levels of foliar zinc. Media porosity, percent air space, and bulk density increased, while water holding capacity decreased with increasing amounts of shredded tire rubber added to the media.
Keywords: geraniums Ebb-and-flood Pelargonium* hortoruml. H. Baileyc foliar zinc