Reducing nitrate leaching losses from turfgrass fertilization of residential lawns

Abstract Fertilizer applications on lawns have raised environmental concerns in many Canadian municipalities. In this greenhouse study, NO 3 –N leaching losses from Kentucky bluegrass ( Poa pratensis L.) were evaluated two soils (a schist loam and a clay loam) sand/peat moss rootzone mix (80% sand, 20% peat moss). Eight different fertilizer N sources (urea, Polyon 8 12‐wk release, Duration 45 90‐d XCU, corn gluten meal, UFLEXX) assessed at five application rates (25–200 kg ha –1 yr ) frequencies over 8‐wk trials. Average concentration leachate measured levels of 3.5, 7.4, 1.4 mg L turf grown loam, clay, sand respectively, but mostly affected by mineralization organic matter. Turf fertilized with ≥100 generally resulted acceptable visual quality both soils, coated‐urea fertilizers more efficient to reduce leaching. UFLEXX urea (150 200 as well XCU (200 higher losses, varying 8.5 23.7 , other consistently below . Our results show that it is possible maintain good turfgrass while keeping low (i.e., <4 selecting the ideal combination source, rate, frequency.