Effect of soil amendments on yield of wild okra (Corchorus olitorius) in northern KwaZulu-Natal, South Africa

Abstract

The consumption of semi-domesticated indigenous vegetables such as Corchorus olitorius is being promoted in South Africa. Presently, cultivation of indigenous vegetables is hampered by the absence of cultivation guidelines due to lack of agronomic research on the various production aspects. The current study evaluated the yield of C. olitorius in response to cattle manure (5 000 kg ha⁻¹) and NPK inorganic fertiliser (500 kg ha⁻¹). Plant height, number of branches, marketable fresh yield and shoot dry mass responded significantly (p < 0.05) to the applied fertilisers. Growing Corchorus without basal fertiliser gave significantly the lowest yield even when top-dressing nitrogen fertiliser was applied. There were significant interactions between the different basal and nitrogen top-dressing fertiliser. It was concluded that the application of basal soil amendments and the interaction of basal and top-dressing resulted in increased marketable yield for C. olitorius. The highest marketable yield for both cattle manure and NPK fertiliser were obtained when these were combined with 200 kg ha⁻¹ lime ammonium nitrate.

Keywords: Corchorus olitorius, nitrogen top-dressing, soil amendment, wild vegetables, yield