Leaching losses of nitrogen, phosphorus and potassium on tobacco soils in north Queensland

Abstract

Abstract A study was conducted in the north Queensland tobacco producing area to examine the efficiency of use of N, P and K on two tobacco farms in the 1987 growing season. A nutrient balance was calculated from soil and plant analysis plus farmer fertiliser applications to estimate the losses of N, P and K which occur through leaching of these nutrients out of the root zone (0–0.45 m). Losses of 110 to 160, 50 to 80 and 160 kg/ha were found for N, P and K respectively during the grand‐growth period from hilling up to first pick. If 75% of these losses could by prevented, savings of $A5000 on an average 20 hectare crop of tobacco could be achieved.