The influence of fertilization on quality of inflorescences of easy pot freesia (Freesia Eckl. ex Klatt) grown from adventitious corms

The experiments were carried out in 2006-2007, in the spring-summer season, in an unheated plastic tunnel. Adventitious corms of Easy Pot Freesia: 'Gompey', 'Popey' and 'Suzy', were the plant material. The influence of a traditional fertilizer Azofoska and slow-release fertilizers, Osmocote Plus 5/6, Osmocote Exact and Polyon 5/6, on the ornamental value of plants was evaluated. All fertilizers were applied at rates of 2.5 and 5.0 g × dm-3. Freesias cultivated without fertilizer were the control plants. The cultivar 'Gompey' was characterized by longer inflorescence shoots and flowers of greater diameter, while the cultivar 'Suzy' had more flowers than the plants of the other cultivars evaluated. Plants with the greatest number of flowers and the longest inflorescences and shoots were obtained when slow-release fertilizers Osmocote Plus 5/6 and Osmocote Exact were used, regardless of cultivar and fertilizer dose. Polyon was useless for freesia fertilization, since it resulted in a decrease of the ornamental value of plants. Plants fertilized with Polyon had fewer flowers, additionally with a smaller diameter, and their inflorescences were shorter and deformed