ISHS Acta Horticulturae 172: Composts as Horticultural Substrates
CULTIVATION OF GERBERA ON SOFTWOOD BARK OF PICEA ABIES AND ABIES ALBA: PHYSICAL CHARACTERISTICS OF THESE SUBSTRATES |
| Author: | D. Pivot |
| Abstract:
Softwood bark (steamed or not) has been composted during 35 days with various levels of nitrogen, and then used for the cultivation of gerberas in 7.5 l plastic pots. Cultivation in bark substrates gives poor results in comparison with a mixture of pest and perlite 90:10%. The main reason for the poor results of bark composts lies probably in their physical characteristics. Before cultivation, the air volume in the composts is about 44% of the total porosity and should be considered as too high in comparison with the volume of easily available water (~ 8%) and the water buffering capacity (~ 1%). These volumes are measured with the method of "pressure plate extractor" for the water tension at 0 – 10 – 50 – 100 cm water suction. The curves plotted after these measurements are compared with the figures given by de Boodt (1972 and 1975), and prove to be very unfavourable. After 252 days of cultivation, the water tension curves of the composts lie in the lower limits of the above-mentioned figures: the physical properties of these substrates, as compared with de Boodt's figures, should therefore be more favourable after than before cultivation. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
