Influence of fertilization on vegetative growth and flowering of the calla (Zantedeschia aethiopica Spreng.)

In Italy, the calla (Zantedeschia aethiopica) is cultivated mostly in Liguria and in the southern regions, because of favourable climatic conditions, but the national production is lower than the continuous demand of consumers. To increase and to improve the production of calla, specific research was carried out to study in detail physiological parameters and to test new cultivation techniques of this species. The experimental trial was carried out to study the influence of nitrogen and potassium fertilisation on vegetative growth and to evaluate the influence of fertilisation levels on flowering, considering qualitative and quantitative parameters. The use of a heated tunnel helped to keep the lower part of the stems and the leaves alive, promoting the vegetative onset in spring and a faster growth of the plant.