coffee valve thinks the people love coffee and drink coffee every day may know many knowledge of coffee,but,they may not know the natural condition of coffee growth.
Not everywhere is suitable for coffee to grow,the place where coffee can be planted is tropical and subtropical zone.The natural condition the coffee need is calm wind,warm cool,shade and moist.So,the zone nearby the equator between 25°S and 25°N is the best place for coffee growth,called coffee belt or coffee zone.
Coffee is originated in Africa,the coffee arabica is native to the tropical high altitude area between 900meter and 1800meter of Ethiopia,the average annual temperature is 19℃.The coffee robusta is native to the tropical rain forest area at an altitude below 900 meter,the average annual temperature of there is 21～26℃.These country of origins are shade or half shade rain forest and river valley area decide the coffee growth need calm wind,shade,warm cool and moist condition.
Different type of coffee have different requirement to the temperature.Coffee arabica needs warm cooler climate,the average annual temperature should be 19～21℃.The coffee tree grow slowly.Coffee robusta needs relative higher temperature ,the average annual temperature should be 23～25℃.Temperature is very important to coffee growth,if the temperature is too low,the tender shoot can not grow normally and it’s bad for blossom and fertilization.On the contrary,the coffee would be also hurt if the temperature is too high.
Generally,the rainfall of the coffee producing area in the world is 1000～1800ml,but some are as little as 760ml while some are as much as 2500ml.The place where rainfall is more than 1250ml and distributed equally is the best place for coffee growth.Long dry season is bad for tender shoot growth,coffee growth is controlled and finally lead to bad harvest.Over rainfall would cause the coffee tree grow too lush trunk,and the rate of blossom and fruit would be reduced.
Light is an essential condition for coffee growth,however,too strong sunlight has a bad impact on coffee growth due to coffee is a kind of half shade crop.Under the strong sunlight,coffee would be sunburned or died.On the contrary,too big shade area would lead the coffee tree grow too lush trunk,the rate of blossom and fruit would be reduced.Coffee growth has different requirement to light in different stages and different situation.Under the precondition of fertile soil and pet irrigation,the shade area can be smaller.On the contrary,if the soil is barren and irrigation is insufficient,the shade area should be expanded appropriate.Generally,the shade area should be 60～70% during seedling period,40～50% before fruiting period and 20～40% during the fruiting period.To ensure appropriate shade,the coffee farmer would plant some shade trees such as banana tree,mango tree,and so on.
Coffee growth needs calm wind condition,typhoon and dry wind are bad for coffee growth.If the typhoon is up to 10 class,the coffee tree be damaged seriously,it can’t fruit well.Besides,the dry wind is bad for blossom.
All the condition talked above is belong to climate factor.Except the climate,geography is the second large factor that has obviously effect on coffee growth.Coffee tree is not suited to be planted in the place where cold current pass,so it’s no doubt that the hillside face south that is calm wind and no frost is the best choose to plant coffee.
Due to coffee tree has a strong root system,it can grow well in a fertile soil condition.Fertile sandy roils and red soils are suitable for coffee growth,while the clay can not drain away water is bad for coffee grow.When the PH is lower than 4.5,the coffee root can not develop well.