Cactuses

The name hedgehog cactusses is given to the wide-ranging genus, Echinopsis (which itself means "appearing like a hedgehog"). At least 180 species fall under the Echinopsis genus, as do many artificial hybrids.

Mature plants are easily recognizable by their cephalium, a wool- and bristle-coated structure at the apex of the plant, containing a mass of areoles from which the small flowers grow. The fruits of melon cactus are pink and resemble the shape of pepper fruits. Melon cactus is a genus of cactus with about 30–40 species. They are native to Americas, with some species along the Andes down to southern Peru, and a concentration of species in northeastern Brazil.

Brasiliopuntia shows thin, slightly shrunken cladodes on a central cylindrical trunk. The leaves are bright green. White areoles bear one or two small brown upright spines. Light brown flowers appear only on adult plants. It is found in Brazil, Paraguay, eastern Bolivia, Peru and northern Argentina, and has become naturalized in Florida among other places.

Strombocactus includes only one species. It has a strong turnip-like root, a small, sunken, roughly spherical stem covered with spirally arranged overlapping tubercles, each with a spine-bearing areole at its tip. Flowers come from new growth at the crown, and the cactus's small seeds are difficult to see with the naked eye. The plant originates from Central and Northeast Mexico.

Queen of the night is a genus of vining cacti, comprising about 18 species, found from the southwestern United States and Mexico. They have a large underground tuber, thin and inconspicuous stems.

Ferocactus are large-sized, barrel-shaped cacti. They have large spines, prominent ribs, and fragrant flowers. As drought-loving plants, they are native to the deserts of North America and Latin America. They are named 'Ferocactus' after their spines, as this term derives from the Greek words for "fierce spines."

Espostoa is a genus of columnar cacti, comprising 16 species known from the Andes of southern Ecuador and Peru. These candle-like cacti are covered with thorns and white hair. In adulthood, a cephalium sometimes appears, similar to the Mexican genus Cephalocereus.

Leuchtenbergia is a monotypic genus. Leuchtenbergia is very slow-growing but can eventually grow up to 70 cm high, with a cylindrical stem which becomes bare and corky at the base with age. It has long, slender, grayish-green tubercles, with purplish-red blotches at their tips. The tubercles are topped with papery spines, making the plant resemble an agave; old, basal tubercles dry up and fall off. After four years or so, yellow, funnel-shaped flowers may be borne at the tubercle tips. The fruit is smooth and green. It has a large, tuberous taproot. It is native to north-central Mexico.

Pelecyphora is a genus of cacti, comprising 2 species. They originate from Mexico.

Artichoke cactus resembles an inverted green pine cone with a woolly center. Artichoke cactus is a genus of cacti with a single species. It is endemic to the state of Tamaulipas in Mexico.

Cleistocactus is a genus of flowering plants in the cactus family Cactaceae. The stems of these cacti are tall, mostly slender and often many-branched with numerous ribs with closely set areoles and spines. The flowers are tubular and the tips hardly open with only the style and stamens usually protruding. Cleistocactus is native to mountainous areas to 3000 m of South America.

Pereskia, as traditionally circumscribed, is a genus of cacti that do not look much like other types of cacti, having substantial leaves and thin stems. Plants are leafy and spiny, treelike, shrubby, and often scrambling. Leaves are generally alternate, broad, flattened, deciduous, usually with petioles, 2 to 20 cm long. The young primary areoles on twigs normally have up to eight spines, while areoles on trunks usually have more (15 to 40, up to 120) straight, usually black spines of unequal length. Flowers are solitary, or sometimes in inflorescences of 2–15 flowers; the flowers are 2 to 8 cm in diameter, usually pink, rose, or purple, but sometimes orange, yellow, white, or cream. Fruits are solitary or in clusters. They are variable in shape, but generally oblong and/or pear-shaped. When mature, fruits usually become green or yellow-green but also orange, reddish, or brownish. Seeds are 2 to 7 mm large, obovate to kidney shaped, and glossy black. This genus includes about 17 species. Pereskia originates from the region between Brazil and Mexico. Most of the species are found in dry forests or thorny scrub, in tropical climates with a dry season of two to five months.

Turbinicarpus is a genus of very small to medium-sized cacti, which inhabit the north-eastern regions of Mexico.

Beehive cactusses are a genus of small cacti native to southern North America. The Latin name of this genus, Coryphantha, derives from Greek koryphe (= head) and anthos (= flower), in reference to the fact that the flowers of these plants arise from the top of the stem. Many species significantly change their form as they mature and are popularly cultivated as house plants.

Ariocarpus is a small genus of succulent, subtropical plants of the family Cactaceae. Plants have thick tuberous tap-roots, and are solitary or form small clusters of stems. The stems have tubercules (as is normal in cacti), but unusually these are triangular and in some species may resemble leaves. The areoles, when present, vary in appearance from grooves on the upper surface to round pads near the tips. Spines are only present in seedlings. The funnel-shaped flowers are borne on a woolly structure at the apex. They vary in colour, from white or yellow to pink, purple or magenta. The seeds are black and pear-shaped. With one exception, the genus is native to the central parts of Mexico, the northeast and the southwest.

Barrel Cactus are a small genus of cacti native to Mexico. They are characterized by their abundance of spines and comparatively small flowers. The special distinction that separates this genus from others is the copiously woolly fruits produced by each plant belonging to this genus. Some members of the genus are cultivated ornamentally thanks to their ease of care, perfect roundness, and interesting spines.

Pygmaeocereus are small cacti native to South America. They are characteristic for their short height, as well as for having complex and fairly large tuberous roots to store nutrients and water. In the blooming season, their attractive, scented flowers open at nighttime. Besides their interesting appearance, pygmaeocereus are hardy and undemanding, so some species are popular houseplants.

Rebutia are small flowering cacti that originate in South America. The genus was given its name 'Rebutia' in homage to the French cactus cultivator, Monsieur P. Rebut. These cacti are petite, globular, and vibrant in color. They produce flowers that are comparable in size to their cactus bodies and grow on hills and mountains in the wild. Many rebutia are popularly cultivated as houseplants thanks to their magnificent blooms.

Genus myrtillocactus is comprised of a small group of handsome tropical cacti. The name means "blueberry cactus" in Latin, and for good reason – one species within the genus, the Bilberry Cactus (M. geometrizans) forms fruits that look similar to blueberries. These cacti are also cultivated as ornamentals.

Cephalocereus are a large genus containing over a hundred species of cacti, all of which are native to the Americas. Many of these cacti are grown ornamentally. Like most cacti, these are arid-climate specialists that are characterized by their thick water-conserving stems and protective outer layer of hairs.

Stenocactus are a genus of cacti that are adored by succulent enthusiasts for their attractively wrinkled leaves and spiny thorns. They are great to grow in containers and flower more readily than many other cacti. These plants are easily identified by their vertical leaf ribs that look like fins.

Night-blooming cactus do exactly what their common name would suggest - they bloom almost exclusively at night, often producing very large, showy white flowers. Many species also produce widely-cultivated edible fruits: dragonfruits. Whether cultivated for food, flowers, or both, night-blooming cactus are favorites among gardeners living in hot, relatively arid climates.

Mammillaria are recognized as cacti with clusters of column-like or spherical stems, mammillaria produce tubular-shaped flowers. They are low-growing evergreens that are often cultivated for containers in tropical climates. Gardeners like them as they are easy to look after.

Hedgehog cactus are small-to-medium sized plants that are easier to cultivate in home conditions than many other cactus groups, with attractive blooming occurring in the spring if the plants are growing in optimal conditions. The "hedgehog" part of the common name "Hedgehog cacti" refers to the shape of its spiny fruits.

Mistletoe cacti are flowering cacti found around the world. They are the only true cactus group that have a natural distribution in the Old World. The genus name Rhipsalis comes from the Greek term for wickerwork, which refers to the plants' looks. Several species of mistletoe cacti are regularly cultivated as houseplants, while some are listed as endangered.

Climbing cacti are unique cacti that lack spines and are not bulbous in structure. They are called "climbing" cacti because they are usually epiphytic, meaning they grow on other plants instead of in the ground. All species bloom with beautiful, fragrant, white flowers at night and many bloom for a single evening only. Some climbing cacti are cultivated for ornamental purposes.