Cestrum is a genus of - depending on authority - 150-250 species of flowering plants in the family Solanaceae. They are native to warm temperate to tropical regions of the Americas, from the southernmost United States (Florida, Texas: Day-blooming Cestrum, C. diurnum) south to the Bío-Bío Region in central Chile (Green Cestrum, C. parqui). They are colloquially known as cestrums or jessamines (from "jasmine", due to their fragant flowers).
They are shrubs growing to 1-4 m tall. Most are evergreen, a few are deciduous. All parts of the plants are toxic, causing severe gastroenteritis if eaten.
Several species are grown as ornamental plants for their strongly scented flowers.
Solanum muricatum is a species of evergreen shrub native to South America and grown for its sweet edible fruit. It is known as pepino dulce ("sweet pepino") or simply pepino; the latter is also used for similar species such as "S. mucronatum" (which actually seems to belong in the related genus Lycianthes). The pepino dulce fruit resembles a melon (Cucumis melo) in color and flavor and thus it is also called pepino melon or melon pear, but pepinos are are only distantly related with melons and pears. Another common name, "tree melon", is more often used for the Papaya (Carica papaya) and the pepino dulce plant does generally not look much like a tree. The present species is, however, a close relative of other nightshades cultivated for their fruit, including the tomato (S. lycopersicum) and the eggplant (S. melongena), which its own fruit closely resembles.
The fruit is common in markets in Colombia, Ecuador, Bolivia, Peru and Chile, but less often overseas because is quite sensitive to handling and does not travel well. Attempts to produce commercial cultivars and to export the fruit have been made in New Zealand and Chile.
The pepino dulce is relatively hardy. In its native range it grows at altitudes ranging from close to sea level up to 3,000 m (10,000 ft.). However, it performs best in a warm, relatively frost-free climate. The plant can survive a low temperature of -2.5° C (27 to 28° F) if the freeze is not prolonged, though it may drop many of its leaves.The species is a perennial, but its sensitivity to chilling, pests, and diseases force the growers to replant the crop every year. The crop also adapts well to greenhouse cultivation, training the plants up to 2 m tall, and obtaining yields that are 2-3 times larger than those obtained outdoors.
They are propagated vegetatively by cuttings since they are established easily without rooting hormones. It is grown in a manner similar to its relatives such as the tomato, though it grows naturally upright habit and can thus be cultivated as a free-standing bush, though it is sometimes pruned on trellises. Additionally, supports are sometimes used to keep the weight of the fruit from pulling the plant down. It has a fast growth rate and bear fruit within 4 to 6 months after planting. It is a perennial, but is usually cultivated as an annual. Seedlings are intolerant of weeds, but it can later easily outcompete low growing weeds. It is tolerant of most soil types, but requires constant moisture for good fruit production. Established bushes show some tolerance to drought stress, but this typically affects yield. The plants are parthenocarpic, meaning it needs no pollination to set fruit, though pollination will encourage fruiting.
Solandra maxima, is a vigorous vine which is endemic to Mexico and Central America. It has very large yellow flowers and glossy leaves.
References : Wikipedia
Here is a collection of the hybrids i grow