Use of organic fertilizers and nutrient uptake of Weigela 'Bristol Ruby' in container culture with a peat-free substrate

摘要

One-year-old rooted cuttings of Weigela cv. Bristol Ruby were grown in containers using a peat-free substrate and organic fertilizers (horn fertilizer, MALTaflor, vinasse) and a slow release fertilizer (6 M Osmocote) in trials conducted in Hannoverand Osnabruck, Germany. In Osnabruck, the Osmocote treatment was combined with a peat substrate. During the vegetation period, shoot and root growth, uptake of N, P, K, and the mineral nitrogen content in the substrate were measured. The mineral nitrogencontent in the substrates was lower upon treatment with organic fertilizers than treatment with Osmocote. Mineral nitrogen was lower in the peat-free substrate than in the peat substrate. Fresh matter of the plants grown with organic fertilizers were significantly lower than that of plants treated with Osmocote. All fertilizers resulted in marketable plants. However, plants treated with horn fertilizer and with MALTaflor had higher root dry weight and a smaller shoot to root ratio than plants treated with Osmocote. The N content (g/plant) of the new shoots were highest in Osmocote-treated plants, followed by MALTaflor and by horn fertilizer. Plants grown with organic fertilizers took up a higher portion of total N until the end of July than plants grown with Osmocote. P contents of the new shoots did not differ for the fertilizers. K contents upon treatment with MALTaflor and Osmocote were similar and higher compared to horn fertilizer.