Landscape Nov. 2006 L-19 Palms for Hawai‘i Landscapes Melvin Wong, Department of Tropical Plant and Soil Sciences alms are important to Hawai‘i landscapes because with a “tropical” theme. In many places over coconut’s Pthey definitely fit the “tropical” landscape theme. range, the mycoplasm disease lethal yellows threatens When people first see palms they may get the impres­ most coconut varieties and other palm species with ex­ sion that all palms look alike. With further study, you tinction. Because coconut palms provide a valuable land­ can gain a greater appreciation of each species and can scape theme, lethal yellows can have a strongly nega­ detect the differences. tive effect on tourism. Florida has battled this disease for decades with some success. Hawai‘i is lucky to not Palm colors be one of the locations that lethal yellows affects. This Palms do not have a great variety of color. But in tropi­ makes Hawai‘i one of the better places to buy palm seed cal themes green is often an important color. Palms can that has no danger of spreading lethal yellows. The be used in the background or as cover for many smaller Malaysian dwarf coconut, called Samoan dwarf coco­ plants that require moisture and shade. A few palms have nut in Hawai‘i (Fig. 7), and many other palm species exceptional color. Cyrtostachys renda (sealing wax palm, are resistant to lethal yellows. The following palm spe­ Fig. 1) has a bright, red leaf base but needs shade and cies are known to be susceptible to lethal yellows: wind protection for best results. In Southeast Asia you Borassus flabellifer (Palmyra palm) will see sealing wax palms in the open with no wind Caryota mitis (fishtail palm, Fig. 8) protection. But in these locations daily wind velocities Cocos nucifera (coconut palm) are low and humidity is high. Another palm with excep­ Dictyosperma album (princess palm, Fig. 9) tional color (orange) is Areca vestiaria (Fig. 2). This Latania sp. (latan palm) clumping palm will do best with some shade. The fol­ Livistonia chinensis (Chinese fan palm) lowing palms are predominately grey: Phoenix canariensis (Canary Island date palm, Fig. 10) Bismarkia nobilis (Bismarck palm, Fig. 3) Phoenix dactylifera (date palm, Fig. 11) Dypsis decaryi (triangle palm, Fig. 4) Phoenix reclinata (Senegal date palm) Latania loddigesii (blue latan palm, Fig. 5) Phoenix sylvestris (wild date palm) Pritchardia hillebrandii (luolu leo). Pritchardia affinis Pritchardia pacifica (Fiji fan palm, Fig. 12) These palms can be used in various ways with other Pritchardia thurstonii (Masai palm, Fig. 13) tropical plants that are grey. Veitchia merrillii (Manila palm, Fig. 14) Veitchia montgomeryana (Montgomery palm). Palms and lethal yellows disease Throughout the tropics and subtropics, coconut palms Bringing palm seeds to Hawai‘i is a very serious viola­ (Cocos nucifera, Fig. 6) are the trees most identified tion of plant quarantine regulations because of the dan­ ger of importing lethal yellows. Published by the College of Tropical Agriculture and Human Resources (CTAHR) and issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture. Andrew G. Hashimoto, Director/Dean, Cooperative Extension Service/CTAHR, University of Hawai‘i at Mänoa, Honolulu, Hawai‘i 96822. An equal opportunity/affirmative action institution providing programs and services to the people of Hawai‘i without regard to race, sex, age, religion, color, national origin, ancestry, disability, marital status, arrest and court record, sexual orientation, or status as a covered veteran. CTAHR publications can be found on the Web site <http://www.ctahr.hawaii.edu/freepubs>. UH–CTAHR Palms for Hawai‘i Landscapes L-19 — Nov. 2006 “Tropical” theme palms Syagrus romanzoffiana (queen palm, Fig. 29) The following palm species can be used to portray a Satakentia liukiuensis strong “tropical” theme: Wyodetia bifurcate (Fig. 30). Cocos nucifera (coconut) These palms also add vertical lines to the landscape. Corypha lecomtei (Fig. 15) When these vertical lines are repeated in sequence the Corypha umbraculifera (talipot palm, Fig. 16) effect can be powerful. The design principle of rhythm Arenga undulatifolia (Fig. 17) and repetition is in play here. Clinostigma ponapensis Clinostigma samoense (Fig. 18) Indoor palms Johannesteijsmannia altifrons (litter collecting palm) Many palms require shade and make good indoor plants. Lodoicea maldivica (coco de mer) The following are commonly used as lobby or indoor Pelagodoxa henryana (vahane palm) plants in Hawai‘i: Pigafetta filaris (pigafetta palm) Chamaedorea emesti -augustii Pinanga kuhlii (Fig. 19) Chamaedorea elegans (parlor palm) Prestoea tobagonis (Fig. 20) Dypsis lutescens (areca palm, Fig. 31) Rhopalostylis baueria Howea fosteriana (kentia palm) Sabal causiarum Phoenix roebelenii (dwarf date palm, Fig. 32) Sabal palmetto (Fig. 21) Ptychosperma macarthurii (Macarthur palm, Fig. 33) Sabal parviflora (Cuban palmetto) Rhapis excelsa (lady palm, Fig. 34) The use of Pigafetta filaris along with ferns provides Rhapis spp. (dwarf rhapis palm). a strong “prehistoric” look. Arenga undulatifolia is one In addition, Asterogyne martiana (Fig. 35), Johannes­ of the most attractive large palms and looks good in teijsmannia altifrons (Fig. 36), and Pinanga kuhlii are parks. I encourage you to get to know the details of the particularly attractive, but they are not easy to find. above palms, so you can use them in various landscape Lyon Arboretum occasionally will offer a class on styles. palms given by Ray Baker. He has recommended that Many palms have been used in a formal way. Many Synechanthus fibrosus (Fig. 37) be tried as an indoor of these palm species are tall and straight and used to plant. Many more chamaedorea palms can be used as line streets and sidewalks. The most famous is Phoenix indoor plants including Chamaedorea metallica (Fig. canariensis (Canary Island date palm). It has been used 38). Laccospadix australasica (Fig. 39) has also been to line streets in Las Vegas (Fig. 22), Stanford Univer­ used as an indoor plant but is not easily found. sity (Fig. 23), and the city of Santa Monica (Fig. 24). Here in Hawai‘i it has not been used extensively. I have Palms as food seen the following palms line streets on O‘ahu: Palms are used for food in many ways. Attalea cohune (between the Capitol building and Iolani • Sago: Starch material from central pith of the trunk Palace, Fig. 25) of Metroxylon vitiense, Caryota urens, Corypha Phoenix canariensis (Schofield military base) umbraculifera, Borassus flabellifer, and Roystonea Washingtonia robusta (Waikele, O‘ahu, Fig. 26). oleracea • Palm sugar or jaggery: This is extracted from the sap of Borassus flabellifer, Cocos nucifera, Caryota urens, Street palms Phoenix dactylifera, and Phoenix canariensis The following palms can and probably have been used Wine: Wine is made from the sap of Borassus to line streets or sidewalks: • flabellifer, Caryota urens, Cocos nucifera, Elaeis Archontophoenix alexandrae (Alexandra, Fig. 27) guineensis, Phoenix dactylifera, Phoenix sylvestris, Latania loddigesii (blue latan palm) and Sabal palmetto Roystonea oleracea (Carribean royal palm, Fig. 28) • Oil: Oil is obtained from Cocos nucifera and Elaeis Sabal palmetto guineensis 2 UH–CTAHR Palms for Hawai‘i Landscapes L-19 — Nov. 2006 • Honey: Honey is obtained from Cocos nucifera and P. kaalae* Rock Oahu Borassus flabellifer P. lanaiensis Becc. & Rock Läna‘i • Cabbage or hearts: Palm hearts are obtained from P. lanigera Becc. Hawai‘i meristem and undeveloped leaf bases and leaves of P. limahuliensis H. St. John Kaua‘i Archontophoenix alexandrae (Alexandra palm), Areca P. lowreyana Rock Moloka‘i catechu (betel nut palm), Bactris gasipaes (peach P. martii (Gaudich.) H. Wendl. O‘ahu palm, Fig. 40), Caryota urens (wine palm, Fig. 41), P. minor Becc. Kaua‘i Cocos nucifera, Hyophorbe lagenicaulis (bottle palm, P. munroi* Rock Moloka‘i Fig. 42), Livistonia rotundifolia (footstool palm), P. napaliensis* H. St. John Kaua‘i Lodbkea maldivica (coco de mer), Normanbya P. perlmanii* Gemmill Kaua‘i normanbyi (black palm), Oncosperma spp., Roystonea P. remota* (Kuntze) Becc. Nihoa oleracea (Caribbean royal palm), Sabal palmetto, P. schattaueri* Hodel Hawai‘i Satakentia liukiuehsis, and Syagrus romanzoffiana P. viscosa* Rock Kaua‘i (queen palm). P. waialealeana Read Kaua‘i Palm fruit: Cocos nucifera, Bactris gasipaes (peach • Those marked with an asterisk are endangered (list cour­ palm), Borassus flabellifer, and Phoenix dactylifera. tesy of Curtis Daehler). Of the 23 native Pritchardia species listed, I am fa­ Coconut is a very versatile food source in Hawaii and miliar with only four. For landscape purposes I like P. other tropical locations. The water in the fruit is a re­ glabrata, P. hillebrandii, and P. martii, and I do not like freshing drink, and the milk obtained by squeezing the P. affinis. grated endosperm is used in many tropical dishes and for making a dessert called haupia. The date palm, Phoe­ Invasive species nix dactylifera, and the fruit from Borassus flabellifer Recent increased awareness of the dangers invasive are also very important economically where they are plants can pose to native Hawaiian ecosystems has re­ grown. The fruit of Bactris gasipaes is the staple starch sulted in evaluation of the invasiveness of plants used in Costa Rica. in landscaping. Based on conversations with experts on I have included my favorite landscape palms for your palms and invasive