Many cacti are propagated easily by cuttings. The great advantage in using this method of increase is the almost immediate acquisition of additional plants of potting size. This is especially true of the jointed species whose branches may be pulled or cut off and quickly rooted. The one lurking danger is rot, against which precautionary measures are imperative.
While almost any part of a cactus will grow new plants tops, ribs, tubercles, or disarticulated branches--only jointed species are recommended to the beginner. The other methods may be employed when experience is riper.
Whatever type of cutting is used, it should be severed from the mother plant with one swift stroke of a sharp knife or mounted razor blade. The cutting should be examined carefully for signs of actual or threatened rot. Any spots or suspicious-looking areas should be dissected out and the wounds soaked in Semesan for half an hour. Place the cutting in a dry, ventilated place until the cut surfaces have become sere (formed a callus). This may take several weeks. Then the cutting is placed in a propagating box of clean sand to root. Very little of the cutting should extend into the sand, and if the specimen is topheavy or unsteady on its feet, it should be tied to a wooden skewer, thrust deeply into the sand, for support. Roots form in varying lengths of time, depending upon species-a week or two in the case of Pereskias and a year or more for Carnegias. In fact, most of the globular cacti are very slow in producing roots. Hybrid cacti, of course, must be increased by cuttings to assure perpetuation of the same hybrid characteristics.