Skyblue clustervine (Jacquemontia pentanthos) is a south Florida native, naturally found only in Collier, Miami-Dade, Monroe, and Broward Counties. It is not a Florida endemic, however, because it is also found in the Caribbean, Central America, Mexico, and Hawaii. In Florida, it is listed as a state endangered species.
This is a species of lower elevation, moist habitats - hammock and wetland edges, and it performs much better as a landscape specimen when given ample moisture. It can withstand extended drought, but eventually declines under such conditions. It also cannot withstand extended periods of inundation. As a coastal plant, it has some salt tolerance, but it is not a coastal dune plant and is not the best choice for such conditions.
Skyblue clustervine is a sprawling herbaceous evergreen vine. The multiple stems coil upwards on adjacent vegetation (or trellises) and may reach lengths of 6-10 feet. Older stems become somewhat woody, but remain thin. The leaves are oval and heart shaped, with deep veins.
Flowering occurs mostly in the winter months, but can occur at any time. Large numbers of sky-blue flowers are produced in the leaf axils. As this is a member of the moring glory family, each flower opens in the morning, but they remain open throughout the day and may be pollinated by sphinx moths active around dusk (according to Roger Hammer). Individual plants can have hundreds of flowers open at one time and are spectacular when they do.
Although quite rare in Florida naturally, skyblue clustervine is widely propagated by commercial nurseries. In the landscape, it is relatively easy to maintain and it makes a wonderful wildflower on a trellis or fence. It is cold sensitive, so don't attempt it too far north of its natural range. Give it good moisture and plenty of sun. It also is not long lived. Thankfully, if it dies, it is not impossible to replace it with another plant.