14 ORNAMENTAL CACTI. 



cacti are terrestrial in their habits and are indigenous to warm, semi- 

 arid regions. The annual rainfall in these regions is very slight and 

 continues for only a brief period. It is difficult to reproduce such 

 conditions in our northern climate, and it is found that cacti can best 

 be grown here by minimizing the action of our abundant rains by 

 having the plants placed in a thoroughly well-drained situation. It 

 is equally difficult to reproduce the conditions in our conservatories , 

 where they are heated artificially, because of the drying effect of the 

 heat. This condition may be largely counteracted by a judicious 

 watering of the soil about the plants. For this group of plants it is 

 not necessary that the soil be very rich, but it is essential that it be 

 very open and thoroughly drained. 



In repotting older plants it is best to disturb the roots as little as 

 possible. Enlarge the drain opening in the bottom of the pot and 

 place over it broken pots or other coarse material to not less than 1 

 inch in depth, to insure perfect, uniform drainage. Over the coarse 

 material put a layer of soil. Remove the plant to be repotted by 

 inverting the pot and gently tapping its rim on the edge of a bench 

 or some such solid structure. The whole body of dirt will come out 

 in a lump. Remove any bits of broken pots that may be attached to 

 the bottom, but leave the soil in place about the roots. The surface 

 soil should be removed if it shows any evidence of containing algae or 

 fungous growths. Place this ball of dirt and roots in the next pot 

 and pack fresh soil about it, leaving sufficient space at the top to 

 receive water. In conservatories pots are apt to become coated 

 with green algse, and old pots especially so, because the spores of the 

 aigse are likely to remain in the pores of a pot from its previous use. 

 Old pots should be thoroughly sterilized, as heretofore explained for 

 the germination pots. After the plant is potted the surface of the 

 soil should be covered with fine gravel to a depth of a 4 t least half an 

 inch. 



The soil about the plants should never be allowed to become abso- 

 lutely dry for any great length of time or the roots will be seriously 

 injured; on the other hand, it must not be kept saturated, but 

 should be kept moist at all times. Any superfluous water standing 

 about the base of the plant or in the soil about its roots is a serious 

 menace, since it acts as a medium through which germs of rot enter 

 the plant and soon destroy it. Cactus plants contain so much liquid 

 that decay works very rapidly through them. When decay is once 

 started it is difficult to save the plant; hence, the urgent necessity for 

 having thorough drainage below the plant and a thoroughly drain- 

 able soil. Failures in the growing of cacti are undoubtedly due more 

 to the neglect of this precaution than to all other causes combined. 



Cacti do not require to be pruned beyond the removal of dead por- 

 tions and to keep the plants in shape within the space allotted to 



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