ON THE CULTIVATION OF VANILLA IN MAURITIUS. 61 



XV. On the Cultivation of Vanilla in Mauritius. By John Horne, 

 Curator of the Botanic Gardens. (Communicated by Dr. 

 Hooker, F.E.S.) 



In forming a Vanilla plantation the following conditions are 

 essentially necessary — shade, moisture, good drainage, and sup- 

 port for the plants. 



No place ought to be selected unless it is shaded either by 

 natural or artificial plantations. If the place be densely covered 

 with trees and undershrubs, it will be necessary to cut down a 

 few of the former or to thin out their branches ; and all the latter 

 that do not prevent a free circulation of air may be allowed to 

 remain. They can be used to support the plants, which may be 

 planted at their roots ; but, for convenience in fertilizing the 

 flowers and gathering the fruit, they should not be allowed to 

 grow high. Shade sufficient to break partially the rays of the 

 sun from 10 a.m. to 4 p.m., is all that is required. Lofty trees 

 with wide-spread branches are the best. These may be fruit- 

 trees planted thin as in an orchard or garden or in a shrubbery 

 (with the points of the branches touching each other), or timber- 

 trees growing in a wood. 



Trees that have thick rough bark which is not often shed are 

 the best : the roots of the plants cling to the bark, and, as they 

 are aerial, they are supplied with a certain amount of nutriment 

 which the plants, from their nature, might not otherwise obtain. 



The preparation of the soil, and good drainage, require attention 

 and care, as on these depends in a great measure the welfare of 

 the plants. No site should be chosen for a plantation where the 

 water cannot run rapidly off the surface or percolate the soil. 

 Therefore, if the natural soil of the place be in any way retentive 

 of moisture, it will be better to prepare the beds for the plants on 

 its surface rather than to dig them out of the soil, as the heavy 

 tropical rains would make each bed a cesspool or water-hole. 

 Beds dug out of the soil can only be recommended (and that 

 not very highly) for elevated sites that have a very light porous 

 texture, through which the water can rapidly drain. 



In preparing the beds above the soil, a good method is to put 

 first a layer of stones on its surface and then cover them with any- 

 thing that will prevent the soil from mixing with the stones and 

 choking the drainage. 



VOL. II. R 



