Longan is one of the top export earners for Thailand with an export value of US$ 201 million in 1997. This compared favourably to the export of lychee in the same year. The longan is gaining acceptance, sometimes in preference to lychee. There are, however, a number of limitations which need to be taken into consideration.
At present longan is mainly targeted for ethnic markets especially those of Asian communities. In Australia and Florida, the demand from ethnic Asians far exceeds the supply. Other communities have yet to develop an acquired taste for longan. Once more people have acquired the taste of longan, there is certainly an increase in its demand. There is, therefore, a need for more promotion of the longan among other communities.
Highly perishable longan fruits have limited distant markets. To extend the use of longan, the fruits can be processed into various products such as canned and dried longan. Dried longan is popular among Asians, particularly the Chinese, who make a refreshing longan drink out of it. Again there needs to be aggressive promotion of the longan drink to other communities in foreign markets.
Biennial bearing is a major constraint for expansion of the longan crop. However, it is probably easier to attain good and stable yields of longan than of lychee. Since these fruits substitute for one another this considerably enhances the prospect of longan. If trees bore regularly, growth would be moderated and it would be easier to prune to keep trees to a manageable size. Small trees, coupled with closer spacing and regular yields would allow production to be intensified. This work has already been practiced in Guangdong Province in China.
Small fruit size may be a constraint for some longan cultivars. However, through planting the right cultivars coupled with proper pruning technique of the flower panicle, large fruit size can be achieved.
Expansion of longan cultivation to tropical regions can be achieved with the existence of superior races of subspecies malesianus, in particular the variety malesianus in Sarawak and other parts of Borneo. This may offer an attractive alternative to the commercial longan for the humid tropical lowlands. In addition there are in existence commercial longan cultivars which are adapted to the constantly high temperature of humid tropical conditions as in the case of the cultivar 'Phetsakon' in Thailand. This cultivar is now planted in non-traditional regions of Thailand. The use of potassium chlorate to produce off-season longan adds to the future prospects of the crop and needs to be encouraged. With off-season production, prices obtained by longan growers will be higher.
In view of the above, there is a bright future for the longan.