Hawaiian Names with Diacritics
- Kokiʻo ʻula
- Kokio ula
- Clay's hibsicus
- Hibiscus newhousei
Names with Unknown Sources
- Newhouse hibiscus
Endangered Species Status
Plant Form / Growth Habit
Mature Size, Height (in feet)
- Shrub, Tall, Greater than 10
- Tree, Small, 15 to 30
Mature Size, Width
5+ foot spread.
Long lived (Greater than 5 years)
- Specimen Plant
Additional Landscape Use Information
Kokiʻo ʻula (H. clayi) are usually more compact shrubs when compared to other native hibiscuses and thus an excellent choice to use in landscapes with limited space.
This native hibiscus also makes a good container plant in 3 gallon or larger pots in sunny locations.
Source of Fragrance
- No Fragrance
Plant Produces Flowers
Additional Flower Color Information
Flower colors range from medium to dark red.
- Year Round
Additional Blooming Period and Fruiting Information
Most kokiʻo ʻula are usually in constant bloom.
Additional Plant Texture Information
Leaves range from over an inch to nearly 4 inches.
- Medium Green
Additional Leaf Color Information
The smooth-edged leaves are green and shiny.
Additional Pest & Disease Information
Plants are prone to sucking insects. Chinese rose beetles can be removed by hand. The native red hibiscuses are just as prone to attract the hibiscus erineum mite as the non-native red hibiscuses.
Fertilize kokiʻo ʻula using a 2-1-3 or 2-.5-3 ratio with minor elements. It is important to keep the phosphorus low because it tends to accumulate and prevents the nitrogen and potassium from working. Minor elements such as magnesium and iron are also important to maintain healthy green foliage. 
Generally this native hibiscus can left as free forming shrubs. Hedges may need some pruning two or three times a year. Clear out dead and diseased wood for minor shaping. For pruned shrubs, they are best kept at 6 to 8 feet tall in a landscape setting.
Soil must be well drained
- Full sun
- Partial sun
Additional Lighting Information
Kokiʻo ʻula can tolerate shade but produces more flowers in full sun.
Plants should be spaced 3 to 5 feet apart. For hedges 2 1/2 to 3 feet apart. Specimen plants should be should be spaced 10 to 15 feet apart.
Protect kokiʻo ʻula from strong winds especially in containers. Fairly slow growing compared with other hibiscuses. [Rick Barboza, Hui Kū Maoli Ola] Will tolerate short periods of drought 
Natural Zones (Elevation in feet, Rainfall in inches)
- 150 to 1000, 0 to 50 (Dry)
- 1000 to 1999, 0 to 50 (Dry)
Additional Habitat Information
Kokiʻo ʻula is found in a few dry forests of eastern Kauaʻi.
The large Mallow family Malvaceae contains some 2,300 species, with notables such as okra, cacao, durian, baobab, kenaf, and cotton. 
There are perhaps as many as 300 species worldwide in the genus Hibiscus. There are six native species of hibiscuses in Hawaii and all but one are endemic.
The Hawaiian name Kokiʻo ʻula is shared by our two native red hibiscuses (Hibiscus clayi and H. kokio).
Hibiscus clayi differs from Hibiscus kokio in a few ways:
- Leaves of H. clayi are smooth, or occasionally toothed only near tip; H. kokio leaves are toothed from below middle to the tip (sometimes smooth).
- H. clayi is restricted to Kauaʻi; H. kokio is naturally found on Kauaʻi, Oʻahu, Molokaʻi, Maui and Hawaiʻi.
- H. clayi shrubs are generally more compact in habit or form than H. kokio.
The generic name Hibiscus is derived from hibiscos, the Greek name for mallow.
In 1928, Albert W. Duvel discovered several small hibiscus trees on Kauaʻi that were damaged by cattle. He brought them into cultivation, which proved to be a new species. Isa and Otto Degener named these plants Hibiscus clayi, after the late Horace F. Clay, a horticulturalist and instructor of botany at Leeward Community College (LCC) on Oʻahu.  A small garden with Hibiscus clayi and a small sign in his honor is on the LCC campus in the front near the Biological Science Building.
Margaret James Roe, in her studies of the genus Hibiscus in Hawaii, found another species on Kauaʻi and thus named it Hibiscus newhousei, but is considered as a synonym of H. clayi. 
Kokiʻo is the name given for this species, and ʻula is red.
With so many flowers nearly always available, Clay's hibsicus makes a beautiful lei. 
 Jill Coryell, Hibiscus Lady
 "Small Trees for Tropical Landscape" by Fred D. Rauch & Paul R. Weissich, page 60.
 http://en.wikipedia.org/wiki/Malvaceae [accessed 10/14/09]
 Endangered and Threatened Wildlife and Plants; Determination of Endangered or Threatened Status of 24 Plants from the Island of Kauai, HI.
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Other Nursery Profiles for Hibiscus clayi