The genus can be divided into two basic groups: The robust Chinese subtropicals which are native to Taiwan and mainland China, and the smaller Indochinese tropicals indigenous to regions in and around Thailand and Laos. 

Rhapis excelsa and Rhapis humilis are the oldest cultivated Chinese species, recorded as prized ornamentals in the Far East as early as the 17th Century. These are characterized by having large thick leaves on sturdy canes 3/4" to 1 1/4" (2 to 3 cm) in diameter which grow more than 8' (2.5 m) tall. Rhapis subtilis from Thailand and Rhapis laosensis are "20th century" species, being discovered and named by Odoardo Beccari in 1910 and brought into cultivation during the last two decades. These have thinner, smaller leaves on narrow canes less than 3/4" (2 cm) in diameter and seldom exceed 8' (2.5 m) in height. Other species were named and described by Beccari and Max Burret during the first half of this century, but remain unknown to the modern world of cultivated plants. However, several of these may be grown by Japanese horticulturists as "misnamed varieties" of R. excelsa and R. humilis. Obviously, the genus needs further study to establish complete order. This difficult project is being undertaken by Dr. John Dransfield and Laura Fitt of the Royal Botanic Garden, Kew, England. 
 

Rhapis subtilis "Thailand Lady Palm"  

Rhapis subtilis was introduced into cultivation by Watana Sumawong of Bangkok during the late 1960s. At that time, Thailand Lady Palm was thought to be a miniature form of R. humilis and was distributed commercially under that name until 1984 when it was recognized by Dr. Dransfield and Ms. Fitt to be Beccari's Rhapis subtilis. 

"Thailand Lady Palm" is a small species, seldom exceeding 6' (2 m) of height. Canes are narrow with neat smooth fiber, brown in color. Offshoots have stiff, brittle roots and sucker close to the main cane, making division almost impossible. Since males and females flower prolifically, abundant amounts of seed are available. 
 

Being a tropical, R. subtilis requires high humidity and abundant moisture. While all Rhapis can attract scale insects, this is the only species severely affected by spider mites. It has a temperature range of 32 to 90 degrees F (0 to 32 degrees C), but prefers 60 to 80 degrees F. Thailand Lady Palm thrives in humid, tropical climates, but seldom adapts to hot dry regions or cool subtropical areas. It can be difficult as a houseplant. 

Rhapis laosensis "Laos Lady Palm"  

First discovered and named by Beccari more than 70 years ago, this small Lady Palm was brought into cultivation during the 1960s by the late David Barry of California. The few specimens in America are all female divisions of his plants and they have not yet been critically identified as R. laosensis. Canes are pencil thin and as with R. subtilis, have slick neat fiber. Thin leaves with wide segments curve downward providing a very graceful effect. One of the oldest cultivated specimens is displayed at Fairchild Tropical Gardens in Miami and stands almost 6' (2 m) tall. 
 

Rhapis humilis "Slender Lady Palm"  

Native to China, this subtropical is the tallest of all Rhapis, often exceeding 18' (6 m) in height. Large leaves with many narrow segments envelop slender canes, creating the name "Slender Lady Palm". 

Some of the first imported into America in the early 1900s are still majestically growing at The Huntington Botanical Garden in San Marino, California. Primarily used as towering landscape specimens on the American west coast, R.humilis thrives in cool subtropical climates with temperatures from 18 to 90 degrees f (-7 to 32 degrees C). Those grown in tropical regions suffer in hot summer heat and can exhibit slow growth and loss of vigor. 
 

Rhapis excelsa "Large Lady Palm" and "Miniature Lady Palms"  

Rhapis excelsa is the most well-known and widely cultivated species, easily adapting to most interiors and tropical or subtropical landscapes throughout the world. It has a multitude of named varieties in green and variegated forms. 

Historically, R. excelsa have been used as classic ornamental palms for more than 300 years. They were cultivated by the Japanese elite in the early 1600s, introduced to Europe in 1774, and became prized American "parlor palms" during the 1850s. The popularity of this species can be attributed to its ease of care, durability, insect resistance, and long life. 

Rhapis excelsa consists of two groups: the common "Large Lady Palm" grown from seed or divisions, and the highly refined "Miniature Lady Palms" developed by Japanese enthusiasts into named varieties by selective cloning. 

The "Large Lady Palm" can grow to more than 14' (4 m) of height. Unlike R. humilis which has tall, slender clusters of stems, R. excelsa clumps can gain enormous width, often having a diameter as wide as their height. In 1939, Fairchild Tropical Gardens of Miami planted twelve single cane divisions 6' (2 m) apart; today, these multi-cane palms stand in a 10' to 12' (3 to 4 m) tall hedge which is more than 9' (3 m) wide and 80' (26 m) long. 
 

The green and variegated Japanese cultivars of Rhapis excelsa, collectively known as "Miniature Lady Palms", were developed through selective cloning of choice, unusual specimens from Taiwan. Each named variety has a unique leaf shape and growth habit. Because of a preference for miniature plants, the Japanese propagate the slowest growing strains and further "dwarf" the palms by restricting root systems in tiny pots, using course sand or small gravel, and limiting fertilizer applications. Below, the 'CHIYODAZURU' in a 5" by 7" (13 by 18 cm) bonsai pot is 10 years old and only 24" (60 cm) tall. 
 

Although some young seedlings of common R. excelsa may first resemble certain named varieties, most will eventually develop the same basic "standard" appearance and leaf shape. In contrast, the named varieties will maintain their distinctive characteristics, a result of long-term selective cloning. 

Variegated Rhapis are seedling sports. Within a random group of 10,000 seedlings, perhaps only five will sprout striped leaves, and of these just one may remain a stable plant and retain a good striping pattern. This is then propagated by division to provide the basis of a new variegated cultivar. In Japan, only a few named varieties display perfect stripes on every leaf; most have random striping patterns - no two are exactly alike. Usually, new offsets will carry the striping habit of the leaf directly above on the "mother" cane. 
 

Japanese horticulturists have developed more than 100 named cultivars. While most of these are varieties of R. excelsa, called KANNONCHIKU, others are green and variegated cultivars of SHUROCHIKU, translated "Rhapis humilis". Although these will eventually reach 6' (2 m) in height and do resemble a delicate, dwarf form of the towering R. humilis grown in California, they may prove to be an Indochinese species more closely related to R. subtilis. Several inflorescences await inspection by Dr. Dransfield and Ms. Fitt, so the mystery may soon be solved. 
 

Rhapis are a fascinating group of palms, having captured the love and admiration of plant collectors for centuries. The charm and elegance of this diverse family of Lady palms provide unlimited choices for everyone... anywhere. 
 

WATERING:  Rhapis should be thoroughly watered by soaking or drenching the entire root system. R. subtilis must be kept constantly moist; if it dries, it will decline or die. R. excelsa, R. humilis, and R. laosensis should be allowed to become almost dry between thorough irrigations. Twice each year, potted Rhapis should be drenched several times (leached) to flush impurities and excess soluble salts. 

SOIL:  Rhapis will grow in almost any well-drained soil, but prefer a mixture rich in humus (pH 5.5 to 7). Pot in African violet type mix or plant slightly above ground level, amending your garden soil as needed. All roots and the base of canes should be covered to retain moisture and stimulate the addition of new offshoots. 

POTTING:  Lady Palms prefer to be slightly root-bound. Soil density should be firm - not loose, not packed - and allow water to slowly filter through. 

FERTILIZER:  All Rhapis are relatively slow-growing plants and need very little fertilizer. As a guideline, apply only 1/2 the recommended rate required by other plants in your home or landscape. Let leaf color be a guide: rich green indicates that fertilizer levels are adequate; apply nutrients when a slight overall yellowish color is detected. 

Rhapis can suffer from trace element deficiencies which produce yellowing leaves, distorted new growth, or general decline. Since the exact cause of a deficiency can often be hard to determine without laboratory tests, use a weak solution of fish emulsion whenever a problem is suspected. 

A WARNING FOR EXCESSES:  Rhapis and many other palms can be highly sensitive to excess boron, fluoride, and chlorine in water supplies, which will cause fast spreading black tip burn. Use the purest water available until the problem is corrected. 

BROWN TIPS:  Slight brown tip fringe is common on all Rhapis. Black tip burn is not typical and can be caused from improper watering, over fertilizing, and other excesses. 

Damaged leaf tips can be trimmed with serrated scissors (pinking shears). Cut in line with the leaf tip, move the scissors slightly sideways and cut again. 

DRIED AND BROWN LEAVES:  Leaf damage is usually caused from extreme heat, allowing the palm to dry out, or not thoroughly watering the entire root system. 

PESTS:  Scale is the enemy of all Rhapis; spider mites are a major problem for R. subtilis. Since scale can hide in the fibrous leaf bases, contact sprays such as malathion are seldom effective. A systemic insecticide which is absorbed into the plant system provides the best protection or control. Since spraying Rhapis in hot summer weather can cause leaf burn, use a systemic insecticide labeled for soil application or spray only during early morning hours. 

ROOT ROTS:  Rhapis are very resistant to pathogens; however, Fusarium oxysporum, Pythium, Rhizoctonia, and Penicillium (pink rot) can periodically infect Rhapis. Use a "broad spectrum" root fungicide labeled as a soil drench to provide prevention or control. 

LETHAL YELLOWING:  Rhapis palms are not known to be susceptible to this fatal disease. During the severe outbreak of L.Y. in Miami, Florida, all species of Rhapis grown in the area remained completely unaffected. 

FREEZE DAMAGE:  Protected Lady Palms can often survive temperatures below their recommended low. The tallest canes may be damaged or frozen, but provide protection for lower, younger offshoots. In extreme lows, all visible canes will die, but new offshoots may sprout by summer. 

DIVISION:  The best time to divide Rhapis is during spring or early summer when the palms are actively growing. Single cane divisions should have at least six leaves and several roots before being separated. Pot into well drained soil using containers just slightly larger than the root system. Remove several lower leaves on each cane to reduce stress. Place in a humid area or mist daily until the palms resume active growth. 

SEED:  Be aware that R. subtilis seed looks exactly like R. excelsa which matches Guihaia argyrata, a recently discovered Chinese relative which sprouts grass-like leaves with silvery undersides (Principes 29 (1). To avoid surprises and a possible mixture of potluck palm seed, commercial growers should know their seed sources. 
 

AIR LAYERING:  Yes, Rhapis excelsa can be airlayered. 

VARIEGATEDS:  Easy to grow, but require excellent culture and good quality water for best appearance and growth. They prefer 70-90% shade or indirect interior light, and temperatures between 60 to 80 degrees R (15 to 26 degrees C) to maintain growth and vigor. Striped Rhapis are slower glowing than green forms and require less fertilizer - too little is far better than too much which may cause leaf burn and root damage. 

LANDSCAPE USE:  Rhapis excelsa adapts to most tropical and subtropical landscapes. R. subtilis thrives in warm, humid regions. R. humilis prefers subtropical landscapes with cool summer nights. 
 

BARRY, DAVID. 1973 Two Rhapis palms from Thailand. Principes 17: 30-32 

DRANSFIELD, JOHN, LEE SHU-KANG, AND WEI FA-NAN. 1985 Guihaia, a new coryphoid genus from China and Vietnam. Principes 29: 1-12. 

MCKAMEY, LYNN. 1983 Secret of the Orient, Rhapis palms. Rhapis Gardens Publications of Gregory, Texas U.S.A. 

MCKAMEY, LYNN. 1983. The Americanization of dwarf Rhapis excelsa. Principes 27: 99-104. 

OKITA, YOSHIHIRO AND LELAND HOLLENBERG. 1981. The Miniature Palms of Japan. Weatherhill. 

YAMAGUCHI, KIYO-O AND DAVID BARRY. 1974. The Culture of Rhapis in Japan. Principes 18: 75-83. 

Note: The back issues of Principes listed above are available at $12 each (postpaid) from the International Palm Society Business Office, P. O. Box 1897, Lawrence, KS, 66044. 

Acknowledgements 

My thanks to Richard Douglas for proof reading this article and for his helpful comments, to Paul Drummond who over the years has shared invaluable information about "Lady Palms", and to my husband Kenneth McKamey who never complains about taking yet another photo of Rhapis for me. 
__________________ 

This article was published in Principes Volume 33: 129-139 (No.3, July 1989).  The journal is now called PALMS and other articles can be found on the International Palm Society's website at www.palms.org 

COPYRIGHT (c) 1989-1999 Lynn McKamey; Rhapis Gardens, P.O.B. 287, Gregory, Texas 78359.  All rights reserved.  This article may not be reproduced in any manner or way without permission.