CROP SPECIFIC APPLICATION RATES OF NITROGEN FOR SOIL-GROWN CROPS IN GREENHOUSES TO PROTECT THE GROUNDWATER

In a desk study, nitrogen (N) fertilizer application rates were studied and N-concentrations at one meter depth or at the drain were estimated for Chrysanthemum grown in twelve greenhouse cropping systems, differing in soil type, supplemental lighting and transmissivity.
Two N-saving strategies were also studied of which one estimated the N-concentration in the irrigation water to comply with the EU target value of 11.3 mg N L^-1. N-surplus varied between 6 and over 709 kg ha^-1 yr^-1. The N-saving strategies reduced the N-surplus but none of the estimated N-concentrations were below the target value.
Growers affect both the N-surplus and the irrigation surplus.
Predefined concentrations are therefore not met if only N-fertilizers are regulated through crop specific application rates.
Guidelines on irrigation applications need to be provided as well.

XXVII International Horticultural Congress – IHC2006: International Symposium on Advances in Environmental Control, Automation and Cultivation Systems for Sustainable, High-Quality Crop Production under Protected Cultivation

A.A. Pronk, W. Voogt, L.F.M. Marcelis

Chrysanthemum, Dendranthema, fertilizer application, balance, irrigation

https://doi.org/10.17660/ActaHortic.2007.761.54