Black Eyed Susan Vine


What you may not know about the Black Eyed Susan Vine

A climbing wall of foliage and flowers is a captivating and refreshing sight in any landscape, yet one classic choice for a vibrant floral wall, the black eyed Susan vine, is sadly underused.



Description of the vine

A climbing vine, the Thunbergia alata is a native plant to Central Africa, where the jungle environment is humid and warm.  Because of this, unfortunately for northern gardeners, the beauty is only hardy in Zones 10 and warmer where the same subtropical conditions exist.  In the southern United States, the vine is able to be grown as a perennial plant; returning year after year to provide their blanket of blooms.  It is not impossible to grow the vine in northern states, but it is only available as an annual plant.

Perennial versions of the vine can reach astonishing heights of over 20 feet, while annual plants can grow up to 8 feet.  The vine grows quickly; featuring dense, lush foliage that is deep green in color.  Blooms will generally begin to appear in early summer, and will continue to emerge throughout the summer.  Flowers are extremely bright and showy; measuring approximately 1 ½ inches in diameter and featuring five petals.  The center of the flower is quite dark, forming the “black eye” for which the plant is famous.  This brownish, purplish black eye is the perfect foil to showcase the pristine white, sunny yellow, soft salmon and pumpkin orange blooms that can provide eye catching appeal right up to early fall.

How to grow

The vine is most often propagated from seed.  In the warm southern United States, the seeds can be sown directly into the soil; northern areas will require the seeds to be started indoors and then transplanted outside after the danger of frost has passed.  This species of plant is a late germinator; taking up to 21 days in some cases for the tiny seedlings to appear.  Full to part sun will provide the optimal results in growth and bloom.  Because of their climbing habit, you will need to provide them with a support onto which they are able to grasp with reaching tendrils in order to climb.  Walls of structures, fences, trellises or even mailboxes or light posts will be transformed into lovely floral displays when planted in these areas.

Another method of propagating the vine is by taking cuttings of the plant.  The plant produces small nubs along its long, twining vines that are capable of developing roots; cutting a piece of this stem and placing it in a glass or vase of clean tap water will encourage this root development.  When the roots have emerged and are approximately 1 inch in length, the cutting is ready to be planted either in a container to keep inside or directly into the soil in warm climates.

Little care is required for the fast growing black eyed Susan vine.  Ensuring that ample water is supplied during the young stage of the plant will result in the best growth, as the plant is fond of moist conditions.  Fertilization, especially for the annual versions of the vine, will help the plant to form the lush foliage that it is known to possess.  No pruning or deadheading is needed, although removing spent blossoms can encourage new bloom formation.  At least in the warmer regions, the plant will re-seed itself.  Gardeners in cooler regions are able to collect the seeds produced by their annuals, however; when properly dried and stored, these will enable the gardener to sow the seeds the following season.

Morning glories are familiar to most as climbing vines that flower profusely, but the black eyed Susan vine should not be overlooked as a beautiful and decorative blooming vine.