Scientific name: Myrtillocactus geometrizans (Mart. Ex Pfeiff.), 1897
Origin: north-central Mexico
Habitat: Chihuahua desert.
Common names: blue candle, blueberry cactus, blueberry cactus
Synonyms: Cereus pugioniferus, Cereus geometrizans, Myrtillocactus grandiareolatus, Myrtillocactus geometrizans var. pugionifera, Myrtillocactus pugionifer
columnar branched cactus candlestick. In nature, it reaches 4.5 m high.
Stems: blue-gray color with a diameter of up to 7-10 cm. They have 5-8 ribs with a depth of about 2.5 cm. The areola is about 2.5 cm apart.
Spines: Each areola can have a maximum of 5-9 spines, but usually has 3-5 short spines (around 5-12mm).
Flower: quite small (2.5-3.7 cm), greenish white, blooms in March, it becomes a very sweet and edible fruit, dark red, oblong, 8 to 20 mm in diameter. Flowering reaches at least 60 cm.
They are hardy, easy cacti, they live well in the soil, the main thing is to make sure that the temperatures do not drop below 4 ° C, but they prefer that the temperatures do not drop below the night. Drop 10 ° C Water regularly in summer, but allow it to dry completely before watering again. It needs a mixture of well-drained soil with gravel and aggregate for good drainage. During the winter months, it should instead be kept dry or limited watering to prevent stems and branches from shrinking. As they are large plants, they need a lot of space for their roots, repotting should be done every two years or so. Exposure: Light shade in youth, full sun after.
Propagation: seeds, cuttings in summer (cuttings root only in the hot season, let the cutting dry well)
Other notes and curiosities: Myrtillocactus geometrizans is often used as a rootstock. It is very easy to grow and is great support for small cacti that tend to rot on their roots or grow too slow (like Ariocarpus and Turbinicarpus)
The crested form (Myrtillocactus geometrizans forma cristata) is highly valued in cultivation, which tends to form fan-shaped ridges that overlap and give a bizarre and sculptural appearance.
There is also a Japanese cultivar: Fukurokuryuzinboku, another very rare and expensive form of monstrous collection. Also known under the English name “Breast Cactus” or “Titty Cactus” due to the peculiar shape of the ribs with nodules that resemble female breasts. Otherwise, it has characteristics similar to the Myrtillocactus geometrizans.