From the Mexican name for some of the Opuntias (Cactaceae). A genus of about 8 species of greenhouse succulent plants, formerly included in the genus Opuntia, natives of Mexico and Guatemala. The plants grow tall and become tree-like. They carry small leaves on new growth which soon fall. They bear few glochids on the areoles.
N. auberi, tree-like growth up to 25 feet, joints long and narrow,pink, Mexico. N, coccinellifera, to 12 feet high, oval joints, rather long, flowers bright red, tropical Mexico. This was used as the host plant for raising the cochineal insect from which the red dye used in food is extracted. N. dejecta, forms a shrub about 6 feet high, straggling growth, flowers red, south Mexico. N. kerwinskiana, tree-like, with long joints, flowers large, reddish pink.
A suitable medium consists of an average potting compost, with added roughage made up of coarse sand, broken brick and granulated charcoal. Repot the plants every two years in spring. Water from March to October as often as thedries out. Keep the pots on a sunny shelf in the greenhouse.
These cacti enjoy more warmth than opuntias, so the summer temperatures should be between 65° and 85°F (18-29°C). In winter water very sparingly, just enough to prevent the plants from shrinking, and maintain a temperature not below 45°F (7°C).
Propagation is by seed sown in John Innes seed compost in early spring. Just cover the seed. Prick out the seedlings when they are an inch high. Or plants may be propagated by cuttings of pads which are freely produced. Dry the base of the pad and set it on a mixture of sharp sand and peat in equal parts. Support the cutting with a stick until it has rooted as the base should not be buried in the mixture.