Nutritional and time of harvesting studies of the poppy (Papaver somniferum L.) on krasnozem soils of Tasmania: nutritional and time of harvesting studies of Papaver somniferum L.

The effects of banded nitrogen and phosphorus fertilizer on the growth of poppies on a krasnozem soil were studied at three different stages of growth; (i) young plants fifty days after sowing, (ii) mature capsules at dry commercial maturity eight weeks after full bloom, (iii) total plant and its components harvested at weekly intervals between full bloom and dry commercial maturity. Higher uptake of banded P and greater plant dry matter yield 50 days after sowing were recorded when the fertilizer was placed 40 mm directly below the seed than when placed 75 mm below. Nitrogen had a negative effect on both uptake and yield in this experiment.