backlit top of a torch cactus (oreocereus celsianus) with red flowers

old man mountain peru bolivia torch cactus drought resistant closeup garden prickly spine spiky flora botany celsianus oreocereus argentina backlit bloom blooming botanical cactaceae cacti cleistocactus cleistocactus tupizensis cultivate desert environment environmental flower foliage furry green grow landscape long nature ornamental outdoor park perennial petal pink plant ribbed spike spiny spring stalks stem succulent