Puʻu Kukui is home to many endemic plants, insects, and birds, including the greensword (Argyroxiphium grayanum), a distinctive bog variety of ʻōhiʻa lehua (Metrosideros polymorpha var. pseudorugosa) and many lobelioid species. Due to the mountain peak's extreme climate and peat soil, many species, such as the ʻōhiʻa, are represented as dwarfs. Access to the area is restricted to researchers and conservationists.