The effect of organic mulch on the growth and yield of Spinach (Spinacia oleracea L)

An experiment was conducted in a greenhouse at the Luyengo campus of the University of Swaziland to determine the effect of organic mulch on the growth and yield of spinach. The experiment was conducted between the months of January and February, 2017. The experiment was a completely randomized design (CRD), with treated sewage mulch (TSM) and organic compost mulch (OCM) as treatments. The no mulch (NML) was used as a control. Spinach seedlings were planted at a spacing of 15 cm within rows and 30 cm between rows. Weeding and pest control measures were done uniformly across the treatments, when and as required. The data collected included the percentage moisture retained by the different treatments on the soil, growth parameters (leaf width, leaf length, leaf number, leaf area, plant height) and yield at harvest. The results displayed a significant difference (P less then 0.05) between the treatments in terms of the moisture retention properties. Organic compost mulch recorded the highest mean percentage moisture retention (22.9%), followed by treated sewage mulch (20.9%) and no mulch recorded the lowest percentage moisture retention in the soil (14.4%). All the growth parameters were higher for spinach growth under TSM, followed by that grown under OCM. They were lowest under spinach grown under no mulch. The differences in mean for parameters were significant (p less then 0.05). The yield also varied across the treatments as TSM had a dry mass of 43.0 g, followed by OCM at 23.4 g and the no mulch treatment recorded a dry mass of 20.9 g. The results showed that mulching improved the performance of the spinach plants in terms of plant growth, moisture retention and yield.