The production of bio-fertilisers and bio-composts is an environmentally friendly way of overcoming the disposal problems of organic wastes especially OPW which are in abundance. The innate fabric of the fibres of OPW is tough and hence very difficult to decompose. However, recent researches have come out with different effective ways of composting and preparing bio-fertilisers from these wastes via enzymatic and chemical means. Most often, PKC is used to enhance the fibres’ decomposability due to their good nutrient contents for making fertiliser. PKCs consist of 6.0% P2O2, 11.0% K2O, 13.5% CaO, 3.5% MgO and 7.5% SO2 (Mohammad et al. 2012). An experiment to investigate the growth of palm oil seed­lings using the same quantities of bio-fertiliser from PKC, normal chemical fertiliser and a control (no fertiliser application) gave frond lengths of 62.03 cm, 53.42 cm, and 28.85 cm, respectively. The petiole dry weights recorded were 0.30 g, 0.25 g, and 0.28 g, respectively (Henson and Dolmat 2003). This clearly shows the high prefer­ence of bio-fertiliser from PKC for healthy plant growth. The overall nutrient con­tents of OPW fibres and PKC make them appropriate for the preparation of bio-fertilisers and bio-composts which many studies have reported (Mohammad et al. 2012; Baharuddin et al. 2009).

POME is also commonly blended with other OPW fibres for composting and fertilisers. Kala et al. (2009) have tested the potency of blending OPT, EFB and OPF with POME for compost to be highly effective. OPT (with POME 4:1 w/w) was found to exhibit properties of a very good compost as potting media for ornamental plants. However, POME alone has been efficiently used for making fertilisers or composts (Siregar et al. 2002) through optimised solid-state fermentation with ther­mophilic fungus, Chaetomium sp. (Yaser et al. 2007).

The fibres from OPW have also been used individually for making composts. EFB is bulky; thus, in order to reduce its bulkiness and make it easier to handle, they are compressed into mats usually called Ecomat (Sung et al. 2010). Ecomat is also found to improve the decomposition rate of the wastes hence producing efficient compost. EFB has fertiliser contents (expressed in kg/ton EFB) of 3.8 kg urea, 3.9 kg rock phosphate, 18.0 kg muriate of potash and 9.2 kg kieserite (Singh et al. 1999) whilst OPF contains 4.4 kg of kieserite, 19.3 kg of muriate, 2.8 kg of rock phosphate and 7 kg of urea/ton (Sung et al. 2010). Compost made from EFB with Trichoderma sp. and supplemented with nitrogen has proven to be of same nutrient values and biode­gradability as compared to chicken manure when they were tested on tomato plants (Mukhlis 2006). Pruned OPFs that are used as mulch as well as for soil conservation in the plantation are found to contribute directly to the supply of phosphates and indirectly by reducing the phosphate sorption capacity in soils (Fairhurst 1996).