Wood fiber as growing medium in hydroponic crop

Fibralur ® is a growing medium that comes from sawmill residues. The substrat has neither resins nor other phytotoxic compounds, and is an organic, stable and sterilized product. In this paper, three trials are showed in order to compare different growing media under hydroponic conditions, in two different crop production areas of Spain. Compared growing media were: wood fibre (Fibralur®), coir and perlite. The first trial was developed in a greenhouse in Northern Spain with tomato crop (cv. Jack). The trial was designed to develop 4 successive cycles in the same bags. Yield, fruit quality, irrigation and drainages solution composition, were evaluated. At the beginning and at the end of the trial, physical characteristics of growing media was also analysed. The experiment started in July 2001 and finished in July 2003 (4 cycles). The results show that during first three crop cycles, there was no differences in commercial yield between growing media. In the last cycle, coir yield was lower than in perlite and wood fibre cases. The second trial was carried out in a greenhouse in Southern Spain, wood fibre and coir were tested in melon (cv. Yucatán) during one crop cycle (March - June 2002). This trial shows that yield and quality fruit are the same in the two treatments, without significant differences. The third trial was carried out in South, in the same place. In this case growing media were compared in tomato (cv. Pitanza). The study took one cycle (30 August 2002-January 2003). Growing media do not show yield significant differences, however, yield wood fibre slightly tends to come early. These results confirm the validity of Fibralur ® as hydroponic growing medium, in the tested crop production areas, being a alternative, with environmental advantages, compared with other non bio-degradable growing media used nowadays.