The Big Island is home to many varieties of ginger plants, most with very striking flowers and exotic fragrance. The Kāhili Ginger (also known as Kāhili Fiesta) is no exception to this, with its huge heads of bright yellow flowers.
You can find the Kāhili Ginger growing throughout the Big Island, and there are many conspicuous stands of the plant on the highway near Volcano, as well as huge quantities within the Hawai'i Volcanoes National Park.
Kāhili Ginger is unfortunately an extremely invasive plant and tends to grow quickly, choking out other native plants. For this reason the park periodically removes huge stands of the various gingers but the effort really has little impact as the plants are everywhere.
The word kāhili means, among other things, the feather standard (large bunch of feathers on top of a tall staff) used in the presence of royalty and it is obvious that this is where Kāhili Ginger inherited the name. Each plant is about 5 or 6 feet tall with beautiful deep blue-green leaves. The leaves are very long and broad and radiate out from the base. A single head of flowers grows off each individual stalk with a single plant supporting up to 20 stalks. Each head is roughly the size of a loaf of bread on end with many rows of bright yellow flowers. Each flower supports a vivid bright red stamen. The flowers range, based on age, from pale yellow to vivid yellow to gold and are extremely fragrant. Indeed, when all the ginger are in full bloom the drive to Volcano can be intoxicating due to the huge stands of white and yellow gingers that line the road.
Ginger is seasonal in Hawai'i and starts blooming in August and continues into the fall. The flower head, when cut, lasts several days in water.
Kāhili Ginger is native to the Himalayas, and it is unknown when it was brought to Hawai'i. It almost certainly came over as an ornamental and quickly escaped local gardens. Because this is an extremely invasive plant, it should be destroyed when found. Since the plant grows from a bulb the entire bulb must be removed from the ground to be properly killed, a very labor-intensive job. The park's strategy, and one that seems to work, is to cut the plants down to nearly ground level and then periodically keep cutting the new shoots off with a weed eater (before they are 12 inches tall). Repeating this for a year kills around 90% of the plants.