Its name was chosen in honor of the Irish botanist William Harris. There are not many species belonging to this genus, and they are easily recognizable by their rather thin stems, furrowed by few ribs and well spaced spines, which allow to see clearly the bright green body. The Harrisia tends to grow rapidly in height, and then transforms its erect shape, in nature, into a dense tangled mat with a very characteristic sprawling habit! An extremely popular feature, loved by a lot of people, is undoubtedly its large funnel-shaped nocturnal flower, which blooms in the evening and closes down at dawn: this is why, as many call it, it is a real "moonlight cactus"! Here are some easy tips for its proper care and cultivation: Put your Harrisia in a sunny spot, however be sure to avoid the direct sunlight during the hottest hours of the day. The minimum tolerated temperature is -4ºC, but just as long as the soil is maintained dry, nevertheless it’s better to shelter them properly in Winter. Water your Harrisia regularly in Summer and less frequently in Autumn, then suspend completely the irrigation in Winter. Always remember to let the soil dry up completely before each watering. We suggest as an ideal substrate a rich, porous, well-draining sandy soil: a standard cacti soil will also do well as a substitute. These are plants that do not need frequent fertilization, it will be sufficient to dilute a specific cati fertilizer with watering once a year.