Ornamental plants are a major component of any outdoor landscape. Adding diversity to the current plant palette provides more color, texture and functional choices, creating new plant combinations and designs. Recent trends in ornamentals indicate a focus on sustainable resource use (i.e. containerized gardening, native and drought tolerant plants and plants serving as pollinator habitats) (ASLA, 2015; Elzer-Peters, 2015; Dizmon, 2016; Polanz, 2016). In Hawaii, there is a need to introduce new ornamental plant cultivars possessing these characteristics. Developing native plants as potted/containerized ornamentals can minimize invasive species risks while promoting Hawaiian culture, the Hawaiian sense of place as well as the importance of conserving local biodiversity. The demand for native Hawaiian plants is expected to rise in the next 20 years, due to recent amendments to HB206/SB435. This state bill aims to gradually increase the use of native plants to 35% of the total plant footprint in new and renovated state and county funded landscaping projects (OHA, 2015). To increase availability and choices of native Hawaiian plants, research must be done to generate information on propagation and growing requirements. Ilima (Sida fallax) is an underutilized native Hawaiian shrub that has potential use as a pollinator-friendly potted flowering plant. It is a drought, wind and salt tolerant shrub that has been mainly utilized as an ornamental groundcover and as a lei material. In Hawaii, ilima is found on all main islands growing from the coasts up to low elevation wet forests (0 to 1,980 meters above sea level) (Wagner et al., 1999). It is a highly variable species exhibiting different degrees of morphological variation within and between populations (Stephens, 2000; Gustafson et al., 2014). In general, ilima can be classified into two morphologically distinct types, with variations in between: 1) the beach type which exhibits prostrate growth and hairy leaves and 2) the mountain type which exhibits erect growth and almost hairless leaves (Stephens, 2000). Native Hawaiians have also identified different ilima forms based on growth habit and flower color: 1) ilima-lei (large, upland type with yellow flowers used for lei); 2) ilima-ku-kula (tall upright form with irregular flowers); 3) ilima-ku-kahakai/ilima papa (low growing commonly cultivated beach form) and 4) ilima-koli-kukui (reddish brown flowers) (Rauch et al., 1997). Despite exhibiting a great degree of morphological variation, there has been very little cultivar development with ilima. Currently, ‘Black Coral’ is the only named cultivar produced in Hawaii. It exhibits an upright and bushy growth, dark stems and flowers roughly twice the size of regular ilima (Taylor, 1998; Tswei, 2001; Yorkston, 2005; Koob, 2012). This cultivar, collected from one locality on Kauai, appears to have diverged from the standard mountain type (Yorkston, 2005). The extreme diversity of growth forms and flowers of ilima provides numerous opportunities for selecting and naming cultivars (Rauch et al., 1997). The aims of this project are to: 1) develop a germplasm collection of ilima obtained from across the state, 2) select and evaluate ornamental forms for use as potted flowering plant and 3) develop protocols for potted plant production.

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