Cultivation of amaryllis (Hippeastrum X hybridum Hort.) is mainly intended for production and commercialization of bulbs for export. Information on amaryllis growth cycle is still inconsistent, therefore this study was carried out to gather data that will contribute to studies on growth analysis of amaryllis var. Orange Souvereign in full sun. The experiment was arranged in a complete randomized design, with 4 repetitions and 10 plants per repetition for each analyzed characteristic. Plants were grown in an area of 2 ha and data were collected monthly over a 14 month period. The leaf area determined at the end of the experiment was on average 3102.65 cm², considering 10 leaves per plant. Bulb diameter increased gradually throughout the period of production, ending, at 420 days after planting, with 9.15 cm on average. Total fresh mass at the end of the cycle was on average 1050.55 g, of which 39 % consisted of bulb fresh mass, which is the traded form (bulb +roots). The physiological indices of the growth analysis showed the plant behavior in the field, under the conditions found in Santo Antonio de Posse, São Paulo State, Brazil, with the assimilatory system having achieved a good performance in these growing conditions. Growth of amaryllis is considered satisfactory in this region, from the point of view of trading , as it can reach the standards required for export.
Floriculture; Hippeastrum X hybridum Hort.; physiological indices; ornamental plants
