Family: Lamiaceae
An invasive shrub that is a landscaping nightmare! While this shrub is considered “pretty” and fast-growing, its beauty comes at a terrible price. Root suckers will appear far from the parent tree, 30 feet away in some cases, ruining the integrity of fences, roads, homes, and grassy green lawns. The aggressive root suckers form monotypic thickets that outcompete other more desirable species.
To date, no naturalized populations have been documented in Hawai’i. Hawaii may lack the correct pollinator to produce viable seeds, or the plants came from a single assession and were vegetatively reproduced. Genetically identical plants are incapable of cross-pollination.
Considered invasive in Puerto Rico and other Pacific Islands, C. quadriloculare has been introduced to many tropical areas through the horticulture trade. Isolated populations were found in Pohnpei, growing in deep shade and forming a monotypic thicket. C. quadriloculare is native to the Philippines and Papua New Guinea and is a woody member of the mint family.
Description and Dispersal:
- A shrub growing up to 12 feet tall
- Bi-colored large leaves (green and purple) with wavy edges
- Leaves are oppositely arranged
- Flower are produced in the Spring and are white and pink
- Flowers bloom in heavy clusters on the terminal ends out of a 3 inch tube
- Dispersed by humans in the horticulture trade and vegetatively by root suckers
High Risk Traits:
- Highly invasive in tropical/subtropical regions
- An environmental weed on several Pacific islands
- Other Clerodendrum species are invasive
- Shade tolerant
- Tolerates many soil types (not limited by substrate)
- Can form dense monospecific stands
- Spreads aggressively via root suckers and bird-dispersed seeds (but fruit production not observed in the Hawaiian Islands)
- Tolerates repeated pruning and cutting
Low Risk Traits:
- Spreads by suckers in Hawaii, but not reported as naturalized
- Unarmed (no spines, thorns, or burrs)
- Limited seed production in some regions due to pollinator dependence
- Herbicides may provide effective control
