Effects of substrate type on plant growth and nitrate leaching in cut flower production of oriental lily

Abstract

Four types of media [coir, 1 coir:1 peat (by volume), peat, and sandy loam soil] were evaluated for their effects on plant growth and nitrate (NO 3-) leaching in the produc-tion of oriental lilies (Lilium L.) 'Starfighter' and 'Casa Blanca'. Twenty-five bulbs were planted in perforated plastic crates and placed on the ground in temperature-controlled greenhouses. The potential for NO3- leaching was determined by placing an ion-exchange resin (IER) bag under each crate at the beginning of the study. After plant harvest (14 to 16 weeks), resin bags were collected and analyzed for NO3- content. Plant tissues were dried, ground, and analyzed for N content. Results indicated that the use of coir and peat did not significantly influence plant growth (shoot dry weight) relative to the use of sandy loam soil; however, substrate type influenced the amount of NO3- leached through the media and N accumulation in the shoots for 'Starfighter', but not 'Casa Blanca'.