The Idria collumnaris (Boojum) originates from the Winter rainfall area (coastal Northwestern part) of Baja California in Mexico (500 km South of USA along the Pacific). The environment is simular to that of the major part of the Western Cape (except Cape Town and direct surrounds). Our seeds were sourced at Cactus Plaza in Holland and B+T in France and virtually all germinated!!!
In June we planted one in a new rockery and, after some hesitation, it starts to grow. When transplanting take care for proper watering. Do not let the soil dry out until the plant starts to grow. This also applies for Fouquieria species such as F. diquetti and F. splendens.The Boojum does not like frost and high night temperatures in Summer. There is however one difference; the soil here is not of vulcanic origin. But this we compensate -since there is a lack of pumice in SA- with slags of coal fired brick furnaces (‘steen oond’). We learned this of an open minded nurseryman in Mauritius. It’s also the way of growing adeniums and other caudiciforms from Madagascar succesfully with less risk of neck- and rootrot.