Lush And Tough Tropicals

Duranta, mandevilla, ruellia, and bougainvillea are the names of just a few of the toughest tropical plants we can grow in our hot summer gardens. To me, the names of these plants sound lush and exotic. I have often thought how much I would love to travel to the tropical countries where these plants grow natively to see them in their natural habitat.

Sky flower duranta
I discovered duranta several years ago in a garden center in Georgia and I simply had to have it. Its tiny, beautiful, most commonly sky-blue flowers hang in rows off the tips of the branches almost like water. Native to South America, it is a member of the verbena family, which is where I’m sure it gets its toughness. It bloomed all summer long in my container, and fortunately was very drought-tolerant given my watering schedule.

I over-wintered it for a few years in my basement with great success, but it took a long time for it to become lush and bloom profusely once I returned it outside. It is said to be root-hardy as far north as zone 7. This means that if you plant it in the ground, it will die back to the ground each winter and return from the base in the spring like many perennials. Officially, Kentucky is hardiness zone 6, but I am certainly going to give this a try.

Brazilian jasmine
Mandevilla sanderi or M. amabilis, the Brazilian jasmine, native to Central and South America, is a wonderful tropical vine that is very commonly found growing throughout Kentucky in the summer. It has amazing 2-inch-long and wide trumpet-like, deep pink flowers and it blooms nonstop all summer. I first saw this plant more than 15 years ago when my sister bought one and planted it near her mailbox.

It will over-winter outside only as far north as zone 8 but more likely zone 10. It is so vigorous that even if you start out with a new small plant in the spring, it won’t be long before it has grown 4 to 5 feet. In its native habitat, it’s not unusual for it to grow 15 feet in length or height. Mandevilla is also available with white flowers, and recently a new red cultivar that is quite stunning can be found.

Blue Mexican petunias
Ruellias, or Mexican petunias, are native to the tropics of South America and Brazil and are grown for their abundance of flowers. The most popular variety with impressive blue flowers is Ruellia brittoniana. The small 1-inch-wide and long trumpet-like flowers are almost a lilac blue and can be found all over this naturally shaped plant. It can grow easily to 3 to 5 feet tall, so plant it in a larger container or in the ground where you will enjoy it all summer long. It looks a bit unkempt in the garden center, but when combined with other annuals in a container or flower bed you will not be disappointed. We planted one a few years ago with ‘Radiation Orange’ lantana in a large flower bed, and after about mid-July we had three or four people a day stopping to ask us what the plant was with the blue flowers.

Bountiful bougainvillea
Last but not least is the bougainvillea, a South American native that is hardy to zone 9. It is most commonly sold in a hanging basket, but really needs a larger growing environment to adequately show off its beauty. Its signature colorful paper lantern-like bracts house the true flowers that can be found in almost every color imaginable. The showy bracts and flowers can be found in large clusters at the end of the branches. It is hard to describe its habit because it is both shrubby and vine-like at the same time. Its stems can become quite woody, so it will not climb on its own and requires training. Most varieties bloom year-round with a resting phase in the winter. To encourage bloom, let the plants dry between waterings and prune back any long gangly growths that emerge. This will also keep the plant more compact and the flowers concentrated because they can grow quite large. This tough, drought-tolerant plant is also easy to over-winter inside. Before winter’s end, cut it back hard and when the new growth emerges in the spring, you will be rewarded with a beautiful plant for another year.

Traveling to far-away countries is a dream of mine, as I am sure it is for many of you. Sometimes I feel very spoiled that I can grow and enjoy all these lush tropical beauties without leaving the comforts of home. I can imagine them for now in their native habitat and enjoy them as they grow at home in my simple, yet beautiful, Kentucky garden.