92 TROPICAL AGRICULTURE CHAP. 



rocks are continually adding to the soil by the weather- 

 ing action of the air and rain and other natural forces. They 

 are also said to retain the heat received from the sun and 

 keep the coffee plants warm during cold nights. 



CLIMATE. The most suitable climate for coffee cultiva- 

 tion is that found in the mountainous regions of the tropics 

 with a range of temperature from 55 F. to 80 F. The best 



Elevation, coffee is grown at elevations varying from 2,500 to 5,000 feet 

 above the sea. The plant is, however, cultivated at much 

 lower levels, and even close to the seashore. But the Ara- 



Not less than bian coffee does not do well under 1,500 feet, and it is ex_ 



1,500 feet 



above the tremely liable to blights and insect pests when grown in 

 these low situations. As nearly all the coffee estates in 

 Dominica were below 1,500 feet, the disastrous blight which 

 ruined the coffee industry of that Island, was probably due, 

 in a measure, to the fact that the climate was not suitable to 



Liberian the cultivation. Liberian coffee, on the other hand, thrives 



coffee a low- 



land plant, best under 1,500 feet : it is indeed a lowland plant, and it 

 may be grown with success in sheltered situations almost as 

 far down as the seashore. An extremely wet climate is not 

 favourable to the coffee plant, and it will not thrive in very 



Exposure to exposed situations. But the exposure can nearly always be 

 modified by shelter-belts of trees ; and, in those countries 



Shelter-belts liable to hurricanes, they are a necessary protection. They 



of trees. . , , , 



must not be allowed to grow unrestrained, however, or they 

 will shade the coffee too much. An annual trimming with 

 the cutlass will not only keep the shelter-belts in proper form, 

 but the small branches and leaves cut off, if buried in the 

 ground between the coffee plants, will rot and form a capital 

 manure for the soil. 



PROPAGATION. Coffee plants are propagated by seed, 

 and the seedlings may either be raised in seed beds or 

 " taken U P from und er cultivated trees, for the seeds readily 

 germinate if placed on damp soil in a shady place, and 



