CULTIVATIOlf. $ 



On the approach of cold weather the plants are brought back 

 into the house and kept quite dry at the roots till the return of 

 spring, when their flowers develop either before or soon after the 

 growing season commences. 



Hitherto we have been dealing with Cacti which have thick 

 fleshy stems ; but there are the genera Rhipsalis, Epiphyllum, 

 and Phyllocactus, which are not capable of bearing a long period 

 of drought, though they may be kept almost dry at the root during 

 winter. In summer they delight in plenty of water, and, when 

 growing freely, weak manure water is good for them. Epiphyllums 

 must be kept always more or less moist at the root. For the several 

 species of Opuntia and Echinopsis, which are sufficiently hardy 

 to be cultivated out of doors, it will be found a wise precaution 

 to place either a pane of glass or a handlight over the plants for the 

 winter, not so much to serve as protection from cold as to shield 

 them from an excess of moisture at a time when it would prove 

 injurious. 



Temperature. 



As the amount of heat required by the different species 

 of Cactus varies considerably, the temperature required by 

 each will be given when describing it. The majority may be 

 kept alive in one house where all would be subjected to the 

 same temperature, but some would then merely exist, and would 

 not flower. At Kew, for example, owing to the arrangements 

 necessary for the public, the majority of the large collection of 

 Cacti are grown in one large house, where the plants present an 

 imposing appearance, but a good number of the species rarely 

 produce flowers. The plants which inhabit the plains of the 

 Southern United States are subjected to a high summer temperature 

 and a cold winter, while those found in Central and South America 

 do not undergo these extremes. 



Insect Peats. 



Notwithstanding the thickness of their skin, all Cacti are 

 subject to attack by various insect pests, especially mealy bug 

 and scale. There is no difficulty in removing such insects 

 from the plants with few or no spines upon their stems ; but 

 those thickly covered with spines and hairs are not so easy 

 to keep clean. The best, cheapest and most effectual insecticide 

 for Cacti is paraffin, its only drawback being the injury it does 

 to the plants when applied carelessly. A wineglassful added to a 

 gallon of soft water, and about 2 oz. of soft soap, the whole to be 

 kept thoroughly mixed by frequently stirring it, forms a solution 

 strong enough to destroy mealy bug. In applying it, a syringe 

 should be used, or, if the plants are to be dipped overhead, car 

 muet be taken to keep the oil thoroughly mixed with the water, 

 or the plant, when lifted out, will be covered with pure paraffin. 



