Plants belonging to the genus Nepenthes often are called pitcher plants or monkey cups. Pitcher plants are insectivorous, or insect-eating, plants that have tubular leaves that resemble a cup or pitcher. Darlingtonia is another genus of insectivorous plants, and frequently Nepenthes plants are confused with Darlingtonia plants. Where Nepenthes plants are not native, growers usually raise them as greenhouse or indoor plants.
Of the 450 known species of insectivorous plants, more than 70 species belong to the Nepenthes genus. Some botanists contribute about 90 species to this genus. They are evergreen perennials from parts of Madagascar, southeastern Asia, Queensland, and other areas in these regions. Generally, they grow in moist, acidic soils in open areas, such as grasslands and often in forests. Many species grow epiphytically, or non-parasitically, on trees.
The pitchers are leaves that are tubular with a hollow pouch. Usually, the leaves are lance- or strap-shaped, ranging from 2 to 26 inches (about 5 to 65 cm) long, depending on the species, hybrid, or cultivar. Each leaf has a stretched-out midrib that acts as a tendril to support the plant. The pitchers grow at the end of some of these tendrils. The pitchers may range from 2 to 14 inches (about 5 to 35 cm) and taller.
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