Question: Please tell us about our state flower. It’s a yellow native Hawaiian hibiscus, right? And where can our ohana go and see it this summer?

— SLL, Manoa

Answer: Yes, our state of Hawaii flower is the endemic, native Hawaiian Hibiscus brackenridgei. A form or variety is found on all of the main Hawaiian Islands. Mao hau hele is its Hawaiian name.

It is rare and endangered, but not because it is hard to grow. In fact, it is quite easy to grow from seeds, cuttings or air layers. The reason it is endangered in the wild is because of chompers and stompers, alien animals that like to eat it and other vulnerable native plants, wildfires, aggressive alien weeds, development of dryland areas and so on.

It is worth growing in our gardens, at schools, at public building landscapes, in parks, hotels and in botanic gardens.

In 1988 our state Legislature designated this special rare plant as our state flower. When Hawaii was a territory, the flower was a red hibiscus, but people were confused: Which red hibiscus? Native or an import? Hybrid or species? So the Legislature, after consulting with us at Honolulu Botanical Gardens and with other plant experts, picked this native plant.

About that same time a pair of intrepid hikers and plant lovers, Jimmy and Nellie Pang, heard about the rare hibiscus from staffers at Waimea Arboretum, and they spent days and weeks hiking and searching in the Waianae Mountains. They found a little struggling plant and brought a sample to Keith Wooliams at Waimea. He confirmed that it was the rare native, propagated it and began sharing it with other botanic gardens.

We got a cutting and grew it at Ho’omaluhia Botanical Garden. I was a student worker then, 19 hours a week, but I always worked more and late because I loved my job, educating keiki and visitors, and growing native Hawaiian plants.

We had a volunteer photographer named Rikki Saito who was on a mission to take pictures of all the plants in the 400-acre garden. She especially wanted to document them all in bloom. The hibiscus was troubling her. We nurtured and waited for it to produce buds and flowers. The timing never seemed to be right; the flowers are fragile and don’t last long. One late afternoon I was still working and I was watching the buds. There was a big yellow one, just about the right stage. As the sun set, the flower opened! I was so excited. I called for Rikki and said, “It’s a working person’s flower, a pau hana bloomer!”

After that Saito knew to take her photographs of the Oahu mao hau hele at dusk. She captured many fine images of this rare and gorgeous bloom. They generally bloom in spring and then rest in summer.

Horticulturally it is wise to thin and prune, and re-propagate the plants from cuttings after they bloom. Minimal fertilizer, especially nitrogen, is also recommended. If you over-fertilize they get too lush and top-heavy, become pest magnets and tend to “huli maka flip down,” or topple over. I have learned to use no fertilizer; I just amend my soil with coarse cinder for good drainage. Cinders as top-dressing are attractive and are also a good slug repellent.

Share the cuttings and new plants widely and we then will have this rare plant into the future. Try to plant it near an outdoor light or a streetlight; this will help minimize feeding damage from Chinese rose beetles, which like to feed on the leaves at dusk.

The Hawaiian name refers to how it self-propagates in the wild. It will grow for about three years, become heavy and topple over, then it will “hele” or travel down the mountain, making a self-ground layer from where the branch is now touching the ground.

Mao is the name for native Hawaiian cotton, and hau is the sea hibiscus, a canoe plant carried here by our ancient voyagers.

Wouldn’t it be great to see this epic plant more widely grown? You can see them at botanic gardens including Lyon in Manoa, Koko Crater and Waimea. The National Tropical Botanical Garden on Kauai also grows and nurtures them.

Heidi Bornhorst is a sustainable landscape consultant specializing in native, xeric and edible gardens. Reach her at heidibornhorst@gmail.com.