| Experiments were conducted to evaluate the effect of earthworm castings (vermicompost) as a substrate amendment for poinsettia (Euphorbia pulcherrima Willd.) and chrysanthemum (Dendranthema x grandiflorum Kitam.) production. Substrates evaluated were created by mixing vermicompost produced from sheep, cow, and horse manures with peat moss: perlite (70:30 v/v) at different ratios. When evaluating these substrates at the recommended fertilizer rate for these crops, most of plant growth parameters measured were greater in those mixtures where vermicompost from sheep was present. These results were not associated with the increased amount of nutrients or more optimal physical and chemical properties in the substrate. When both plant species were grown at 0, 50, 200, and 350 mgL−1 N fertilizer rates, greater plant response was observed in substrates where casting from sheep was present. When vermicompost was present in the mixture, it was possible to reduce the amount of chemical fertilizer needed to produce a high quality plant for both species as compared to the controls used in the experiment. Vermicompost was proven to be a successful peat moss alternative as a plant growth substrate for poinsettia and chrysanthemum production. |
