PREPLANT SLOW-RELEASE FERTILIZATION OF STRAWBERRY PLANTS BEFORE FERTIGATION

The advantages of pre-plant fertilization were studied by using a slow -release fertilizer (nitrophoska permanent) with strawberry plants (Fr agaria ananassa, cv Chandler) before fertigation. A sandy soil was use d in the experiment in conditions of abundant rain. When the slow-rele ase NPK was mixed with soil, the leachate analysis of a glasshouse cro p showed a lower loss of N and therefore a lower degree of ground wate r contamination compared with the traditional NPK fertilizer. However, when the fertilizer in question was placed at 10 cm from the surface, as in the case of ornamental plants, the results were less favourable . Consequently, the slow-release fertilizer mixed with the soil not on ly increases the N uptake by the plant as well as the leaf and root we ight, but it also produces higher yields.