Scientific Name: Lobelia agauana E. Wimm.
Plant Type: Herbaceous perennial
Environment: High altitude forests of Central America
Bloom: Large red bearded flowers with a central yellow stripe on the lower petal
Uses: Plant in a sunny spot in the garden as a treat for hummingbirds.
Mesoamerica Cloud Forest beds 14A and 25C
The Mesoamerican Cloud Forest collection is home to many interesting and exotic plants grown from seeds collected in Central America. Among the most spectacular is Lobelia aguana, a shrub collected from the slopes of Vulcán Zunil in Guatemala where it grows between 7,000 and 8,000 feet. It can be found throughout Honduras, Guatemala, and Southern Mexico. This rarely collected plant was introduced to cultivation by the San Francisco Botanical Garden. After losing our specimens, we are happy to reintroduce this amazing shrub to the garden thanks to local seed saving and sharing and the efforts of gardeners and nurseries to preserve the plant in many locations.
Lobelia aguana has clusters of two-lipped tubular flowers, a bright strawberry-red upper lip made of two fused petals and a tangy orange-yellow lower lip made of three fused petals. The flowers bloom along the upright stems, poking out between the leaves like smiling bearded faces. The leaves are long and linear, and when paired with the flowers, give the plant a distinctly tropical appearance. Lobelia aguana grows exuberantly in the Bay Area and will mature into a large 5 foot by 5 foot mass within a couple of years.
Like many other lobelias, Lobelia aguana is a wonderful pollinator plant. The long, red tubular flowers with the lower lips provide butterflies a perch to enjoy the nectar—although they have to compete with the hummingbirds who adore the blossoms just as much!
Most lobelias also contain the chemical lobeline, an alkaloid similar to nicotine. In the past, different lobelia species have been used medicinally for a variety of needs, from tobacco replacement to aiding in cardiovascular disease. However, the toxic dose of lobeline is very close to its therapeutic dose, making it a risky compound to treat people with.
There is much to be explored about the properties and potential uses of plants such as Lobelia aguana, as well as more to be learned about their role in their native habitat. With the combination of climate change and increased habitat destruction by humans, it becomes increasingly important to study these plants both in-situ and ex-situ. The San Francisco Botanical Garden works to preserve plant diversity and knowledge around the world by cultivating and sharing plants like Lobelia aguana so that their value is never lost.
IN BLOOM CONTRIBUTORS: Text and profile by Sarah Callan. Photos by Joanne Taylor.