T. Breimer, C. Sonneveld, L. Spaans
In the Netherlands samples of glasshouse soils are analysed by means of the 1 : 2 volume extract. This extraction method is also used in other countries. Up till now no system was available with which fertilizer applications based on analytical data of this extract, could be calculated with the aid of a computer programme.

This paper presents a system with which recommendations can be made for the use of fertilizers as top dressings. The system is based on concentrations of N, S, P, K, Ca and Mg in the 1 : 2 volume extract. A standard nutrient solution is used, the composition of which differs among crops. The compositions of these standard nutrient solutions are adjusted compensating imperfections in the chemical composition of the soil extract. The concentration of the nutrient solution applied is assessed on the basis of the nitrogen concentration in this solution and in the soil extract. An outline of the calculations is presented.

Breimer, T., Sonneveld, C. and Spaans, L. (1988). A COMPUTERIZED PROGRAMME FOR FERTIGATION OF GLASSHOUSE CROPS. Acta Hortic. 222, 43-50
DOI: 10.17660/ActaHortic.1988.222.5

Acta Horticulturae