THE USE OF COMBINED NUTRIENT SYSTEMS TO CONTROL NUTRIENT LOSSES

A. van Peer
Kalanchoe pot plants were grown on a commercial nursery. Plants were fertilized with a controlled release fertilizer (CRF) Osmocote®Plus 10+11+18+traces (longevity at 21°C 5/6 months) and a water soluble fertilizer (WSF) Peters® Excel CalMag 15+5+15+7 CaO + 3.3 MgO + traces. The Osmocote® Plus was mixed into the substrate at a rate of 2.5 kg per m3 before planting. The water soluble fertilizer was applied between day 21 and day 70 via the overhead irrigation system with EC values varying between 0.7 and 1.1. In the final stage of the culture only clean water irrigation was applied via ground hoses. No additional fertilizer was needed to finalize plant growth until the selling stage. Optimal rate of fertilizer was based on a calculated nutrient release from Osmocote® Plus and topped up with water soluble fertilizer rates depending on soil sampling results. The outcome of the trial was used to calculate the total need of nutrients from the whole nursery (14,000 m2) and compared with previous used fertilizer systems like A-B system with single fertilizers and water soluble NPK fertilizers only.

The results suggest that the use of this combined fertilizer system reduces the total amount of fertilizers by 66% versus A-B system and by 36% versus water soluble NPK fertilizer.

van Peer, A. (1995). THE USE OF COMBINED NUTRIENT SYSTEMS TO CONTROL NUTRIENT LOSSES. Acta Hortic. 401, 347-350
DOI: 10.17660/ActaHortic.1995.401.41
https://doi.org/10.17660/ActaHortic.1995.401.41
recirculation, environment, shelf life

Acta Horticulturae