Diseases and Pests Affecting Cacti and Succulents
are subject to few diseases. The worst is Rot. This is due to stagnant or dripping water or to some neglected wound.
First correct the cause by improving theor drainage, then with a sharp knife cut out the rotted portion. The healthy tissue will skin over and heal.
Another disease—rare, fortunately, in England—is “Orange Spot.’’ There is no known cure, and unless the plant attacked is at once destroyed, the disease may spread through a whole collection.
Pests are not numerous; the thick skin is a deterrent. Mealy Bug is the most common. This is a grey, fluffy insect, oval in shape with many legs. It likes to dig into the areola? And spine clusters, and its position is betrayed by a spot of white fluff—which is almost certain to be bug and eggs.
The better, though more tedious, way to deal with it, is to pick off the insects with a pin, taking care not to prick the plant. Alternatively paraffin can be used, but it may result in the death of the plant too. The safest method is to use one-third of an eggcupful of paraffin to a pail of water, well swished round. If the paraffin is allowed to clot together it clogs the pores of the plant, so it must be kept well agitated. Into this dip the plant bodily for a few seconds, and then plunge it into clean water to remove all traces of paraffin.
A white insect which burrows into the roots is best dealt witn by cutting off the affected roots and burning them. The plant is left on a dry, warm shelf to heal, then the soil is changed and the plant repotted.