Edited sentence: An other reason is probably that most people financially capable (most of the Africans/Asians are not) of setting up such orchards live in these western countries and have never heard from it (because there's no education about it).Besides the extremely delicious fruits, fruits from temperate climates can also be used, and can be crossed to make usage of the year round growing circle, available in the tropics.Having described above that many tropical crops are not frequently planted, the link gives you a list of the tropical horticultural crops.In fact, the only tropical crops that most people know are the common tropical crops (see "common tropical crops").In fact, there are hundreds of types of fruit-bearing plants that can be planted.In the (sub-)tropics, many more (fruit-growing) plants can be planted than in temperate zones.It is however remarkable that the enormous potential of this area lies unfulfilled.It would be wiser to plant the indigenous crops and extend the market of these in the west.Last reason is of course the market, the demand of such crops is not very high, and thus allot of people do not dare to start such orchards for they fear they will not be able to sell their products (for a good price).Some examples of the unused potential:.Some fruits are already make practical usage of these possibility such as the Hess cultivar of the Avocado tree.Such approach would not only increase the diversification of fruit on western markets, but it would also be better for the environment if no exotic (european/american) species are planted in the tropics (this combined with polyculture would of course even be better).The demand of these crops are almost all regional (cause there the only one's knowing the products) and thus the market stays domestic as well.The latter resulting in western backed agricultural education not suited for the tropical countries, and orchards backed by western assistance practically always being common monocultures such as banana, avocado, ....This could be part of the fact that there is no education given in Western countries about such plants.on the border of the Sahel rice can be planted, but instead Africans are planting millet