Organic and Mineral Soil Fertilisation in Gladiolus

Abstract

Research was undertaken for the purpose of assessing, from a bioagronomic point of view, the effect of some organic fertilisers, obtained from purified urban wastewater sludge and of biodegradable mulch on the growth and yield of gladiolus cut flowers, with a view to promoting the development of a sustainable floriculture in Mediterranean environments. The use of sludge + straw-derived compost induced the earliest on the mean flowering period, even through mulching; in any case, the soil supplementation with organic matter only, or added with mineral fertilisers, increased the yield of cut flowers, as compared to mineral fertilisation only. The highest value was obtained by applying sludge + stalk-derived compost; the stem quality, notably the total length and spike length and the number of flowers, was positively influenced by the use of both mineral and organic matter fertilisations, in particular the sludge + stalk-derived compost, either single or mixed with mineral fertilisers. The results obtained seem to prove the effectiveness of the use of purified urban wastewater sludge composted with different organic matrices in floriculture.