MANURING OF ROSES GROWN IN PEAT MOSS
The ideal proportion of the major elements in question, together with the corresponding optimal dose were investigated in relation to the fresh weight of marketable cut flowers. The nutrient content of substrate extracts and plant leaves were analyzed for diagnostic interpretation. Highest yields were obtained with the ionic proportion (meq % anionic and cationic nutrients) : 64 N - 18 S - 18 P - 38 K - 26 Ca - 36 Mg at an optimal dose of 510 meq per plant.
Treatments of the above composition and showing a ratio anions:cations equal to 1:3 gave the most satisfactory results.