By Ralph E. Mitchell
It is always in the nature of the gardener to find new flowering shrubs to add to their landscape collection. One such plant that I am looking at is the King’s Mantle, also known as Thunbergia erecta. This plant from tropical Africa is an interesting and versatile shrub and it is Florida-Friendly Landscaping™ approved!
An average sized shrub of no more than six-feet tall and six-feet wide, the King’s Mantle is easy to fit into any landscape. The evergreen two-inch long oval foliage alone makes for a nice, easy-to-manage hedge. This foliage is well-accented with one and one-quarter of an inch-long royal purple to blue flowers featuring yellow throats – arranged singly or in clusters. Now, as variety is the spice of life, the King’s Mantle also comes in cultivars with white flowers as well as one called ‘Fairy Moon’ which is light blue in color with white-edged petals. This shrub is a fairly fast grower and will technically flower year-round, but with exceptional blossoming in the summer. The flowers have a slight fragrance and tend to be purple in color in sun, and more blue with some shade. King’s Mantle prefers hardiness zone 10, so it will tend to do better closer to the coast or normally warmer micro-climates. However, it is not very salt-tolerant, so keep it away from direct coastal exposure.
As the King’s Mantle is a relatively mid-sized shrub, in the right place it can be maintained without pruning at five to six feet tall. Planted at thirty-six inch centers, King’s Mantle can be installed along porches or near foundations.
In an effort to cross reference planting materials to make sure they are not invasive problems; the King’s Mantle has not been documented by the UF/IFAS Assessment of Non-native Plants in Florida’s Natural Areas to be a problem. The King’s Mantle is also not listed on the Florida Exotic Pest Plant Council’s 2019 List of Invasive Plant Species. And, and mentioned above, it is also a Florida-Friendly Landscaping™ recommended plant to boot!
The King’s Mantle is another potential plant in your landscape palette that you might consider. While I have seen the purple cultivar in local garden centers, you may have to search on the Internet for mail-order sources of the more exotic color selections. To learn more about this shrub and other similar floriferous plants, please call our Master Gardener volunteers on the Plant Lifeline on Mondays, Wednesdays and Fridays from 1 to 4 pm at 764-4340 for gardening help and insight into their role as an Extension volunteer. Don’t forget to visit our other County Plant Clinics in the area. Please check this link for a complete list of site locations, dates and times – https://sfyl.ifas.ufl.edu/media/sfylifasufledu/charlotte/docs/pdf/Plant-Clinics-Schedule1.pdf. Ralph E. Mitchell is the Director/Horticulture Agent for the Charlotte County Extension Service. He can be reached at 941-764-4344 or email@example.com.
Gilman, E. F. (1999) Thunbergia erecta. The University of Florida Extension Service, IFAS.
Landre, C. Thunbergia erecta ‘King’s Mantle’ South-Florida-Plant-Guide – https://www.south-florida-plant-guide.com/thunbergia.html
Thunbergia, Bush Clock Vine, King’s Mantle ‘Fairy Moon’ Dave’s Garden – https://davesgarden.com/guides/pf/go/112741/
Florida Exotic Pest Plant Council’s 2019 List of Invasive Plant Species – http://bugwoodcloud.org/CDN/fleppc/plantlists/2019/2019_Plant_List_ABSOLUTE_FINAL.pdf.
UF/IFAS Assessment of Non-native Plants in Florida’s Natural Areas – https://assessment.ifas.ufl.edu/.
The Florida-Friendly Landscaping™ Guide to Plant Selection & Landscape Design (2010) The University of Florida Extension Services, IFAS.