Cinnamon (Cinnamomum verum J. Presl) bush architecture as affected by modified planting systems

Cinnamon (Cinnamomum verum J. Presl) is a spice crop native to Sri Lanka which plays a vital role in the country's export earnings. Bark being the harvestable portion, the production of cinnamon can be affected by its bush architecture. Hence, this study was conducted to identify the impact of harvesting interval, spatial pattern, and type of planting material on some essential aspects of cinnamon bush architecture, namely, the number of stems per plant, stem height, stem diameter, straightness of the stem, percentage of branches in upper, middle and lower levels of the stem, number of branches per unit length, branch length and angle. Seedlings and vegetatively propagated plants (VP) of cinnamon variety Sri Gemunu were planted under three different spatial patterns such as (A) 1.2×0.6 m with three plants per hill, (B) 1.2×0.4 m with two plants per hill, and (C) 1.2×0.2 m with one plant per hill while maintaining an equal plant density. Two main plots were maintained with the above treatment combinations, harvested according to two harvesting intervals (6 and 8 months). The study was conducted two years after the first harvest. According to the results, seedlings established in the spatial pattern C produced a significantly higher (p < 0.05) number of longer stems with fewer branches per unit length. Similarly, seedlings harvested in eight months intervals produced significantly longer stems (p < 0.05). The stem diameter of VP was significantly higher than seedlings (p < 0.05). Similarly, stem diameter was significantly higher when harvested in eight months intervals than six months intervals (p < 0.05). Seedlings were straighter than VP. Therefore, a preferable bush architecture can be obtained in cinnamon plants by selecting an optimum combination of harvesting interval, spatial pattern, and planting material.