Richard Bogren, Owings, Allen D.
Princess flower (tibouchina) includes several species.
One of the lesser known species is glory flower (T. grandifolia), also known as big leaf tibouchina. It has much larger leaves and larger flowers than the other commonly grown princess flowers. Considered a tropical or tender perennial, the plant is winter-hardy most years in U.S. Department of Agriculture hardiness zone 9A, which is generally south of I-10/I-12.
Purple flowers start in late summer and continue through fall. Plants can be easily rooted using softwood cuttings. A few garden centers in Louisiana sell this plant, which needs to be used more.
A smaller-growing version is called Athens Blue or dwarf tibouchina. We have been growing it at the LSU AgCenter the past five years, and it is a great landscape performer with profuse blooms from late spring through fall on 18- to 24-inch-tall plants. A variegated-foliage form of this plant is now available.
The LSU AgCenter and the LSU College of Agriculture