36 SPICES 



CHAP. 



to cool, it is used for manuring. This burnt earth is 

 very suitable for such plants as vanilla and pepper, 

 which require much potash. 



A certain quantity of lime is recommended to be 

 added to the burnt earth and leaf -mould, especially 

 where soils are deficient in this element. 



Animal manure, such as cow-dung, is not recom- 

 mended. Orchids of all kinds seem to dislike any 

 animal manure, and vanilla is no exception. Should 

 farmyard manure be used, it must only be very old 

 and well-rotted stuff, and then but little should be used 

 mixed with the leaf -mould. Some planters have 

 recommended that in cases where the soil is stiff and 

 clayey, and deficient in humus, trenches 3 or 4 ft. 

 long and 1 or 2 ft. deep should be dug and filled 

 with leaf-mould and sand to above the level of the 

 ground (to allow for sinking), and the vanillas should 

 be planted there. Most planters, however, condemn this 

 proceeding, as the holes are liable to become water- 

 logged. Vanilla is a surface feeder, the roots spreading 

 between the humus and subsoil, so that practically 

 the only feeding ground of the plant is the humus 

 layer. 



Macfarlane even is inclined to condemn digging or 

 ploughing previous to planting, preferring to leave the 

 humus layer on the top of the soil unmixed with the 

 subsoil. Any rotting vegetable matter, such as the 

 leaves and stumps of bananas, coco-nut leaves, grass, etc., 

 should be thrown on the surface and allowed to decay 

 there. 



The amount of manuring required naturally varies 

 with the nature of the subsoil and the depth of the 

 humus. In Tahiti, Bourbon, and Mexico, where the 

 vanilla is cultivated, the soil is volcanic, and conse- 

 quently richer than the stiff alluvial clays so commonly 

 met with in many tropical regions. In the latter class 

 of soils vegetable manures of the character above men- 

 tioned are necessary. 



In the Colonial Report of the Seychelles for 1905, 



