Blue Myrtle

Blue Myrtle (Myrtillocactus geometrizans) grows best when its natural cycle of strong light, freely draining soil and measured watering is respected. Give it full direct sun. Water it according to its seasonal needs: moderate in summer; keep dry through winter. Plant it in fast-draining cactus mix with added pumice. A container with an unobstructed drainage hole is essential, because moisture lingering around cactus roots can quickly lead to rot. Keep its temperature needs in mind: 5–35°c. light frost survivable when dry. During active growth, check the compost before watering rather than following a rigid calendar, since heat, light and pot size all change how quickly it dries. Reduce watering during cool or dormant periods, keep the plant well ventilated, and wait until the growing medium is dry before watering again.

Cuttings root readily after a week's callous. Take material from healthy growth with a clean blade or tongs, then leave the cut surface in a dry, shaded place until it forms a firm callus. Set it into a dry, gritty medium and introduce water sparingly only after roots begin to develop. Young cacti are especially vulnerable to excess moisture. Use a small pot with excellent drainage, provide bright filtered light while roots establish, and move the new plant gradually into the light, temperature and watering conditions preferred by a mature Blue Myrtle.