Possibility of staggered fruit production of rambutan (Nephelium lappaceum L.) in Kerala, India

The study was conducted at Kerala Agricultural University, Kerala, India with the main aim of categorizing cultivars with respect to their flowering and fruiting period. The study was conducted from January to October, 2015 in the entire rambutan growing tracts of Kerala state including Pathanamthitta, Kottayam and Trichur districts besides a minor area in the hilly Wayanad district. Flowering and fruiting were greatly influenced by the prevailing climatic conditions of the particular location. Flowering was earliest in Trichur (end of January to mid of March) followed by Kottayam (end of February to end of March), Pathanamthitta (mid of March to end of April) and Wayanad (June to July). Within Pathanamthitta, two distinct flowering periods were observed, one typical of the plain (end of March to end of April) and the other on the hilly region (May). Fruiting and harvesting were a reflection of the flowering period. Plants came to harvest in May in Trichur, in June in Kottayam, in June-July in plain of Pathanamthitta; however, under the hilly conditions of Pathanamthitta and Wayanad district, it came to harvesting stage in August-September and in October, respectively. The study opens out a new area on the availability of fresh fruits from May (if cultivated in humid tropical plains as in Trichur, Kottayam and Pathanamtitta), to August-September (if cultivated in hill tracts of Pathanamthitta) to October (if cultivated in humid sub-tropical belts as in the high ranges of Wayanad). Therefore, in the near future, the fresh rambutan fruit will be made available for a half-span period of a calendar year.