Search Results
You are looking at 1 - 1 of 1 items for
- Author or Editor: Barbara Whitish Kuyper x
Abstract
Clay foam, a recently patented clay-perlite-vermiculite potting mix that dries to a rigid, lightweight structure, has the capability of retaining nutrients, with the exception of NO3 −, over a long period of time due to the ion exchange capacity of the clay fraction. Isobutylidene diurea (IBDU, 31-0-0), ureaform (38-0-0) and oxamide (31.8-0-0) were evaluated as slow-release N sources for clay foam, utilizing ‘America’ spinach (Spinacia oleracea L.) as a greenhouse test crop, at rates of 0.112, 0.225 and 0.337 g N/3600 cm3 clay pot. A basic nutrient formulation, including enough soluble N to cover the lag period between application and release of the fertilizers, was added to the clay fraction prior to mixing. IBDU showed the greatest potential for use in clay foam, as indicated by fresh and dry weights, total N in the dry leaf tissue and low NO3 − accumulation.