Fruits, Nuts, and Beverage Crops June 2013 F_N-25 Lemons in Hawai‘i Ken Love1, Robert E. Paull2 1Hawaii Tropical Fruit Growers Association, 2Tropical Plant and Soil Sciences emons are just beginning to them following the empire’s dis- get the respect they deserve in integration. Lemon, along with Hawai‘i.L We are fortunate enough citron and sour orange, again made to have numerous varieties to grow, its way slowly westwards back into market, and use for a myriad of Europe between 500 to 1300 AD culinary creations. Almost 14 by way of invaders and travelers, million tons of lemons are grown including the Muslim armies, Arab worldwide, with India and Mexico traders, Crusaders, and travelers being the largest producers. In along trade routes. These early Hawai‘i, we grow and sell less than lemons may have been bitter and 100,000 pounds and still import used as condiments. By the end of almost 4 million pounds. the 12th century, lemon had spread The scientific name of lemon throughout the Mediterranean. is Citrus x limon; the “x” indicates In 1493, Columbus brought it to it is a hybrid between different Hispaniola, and from there it went Citrus species. The taxonomy and with the Spanish to California in systematics of the Citrus genus is 1751. Lemons were reported arriv- complex, and the number of spe- ing in Hawai‘i with Captain James cies is much debated. Some have Cook in 1778 and again with Don suggested that there are only three Francisco de Paula Marin first in valid citrus species: citron (C. medica L.), mandarin 1813, with other varieties arriving with traders in 1823. (C. reticulata Blanco), and pummelo (C. maxima). The Early territorial reports from 1904 to 1906, including remaining Citrus, such as lemon, are from natural hy- the USDA’s “Citrus in Hawaii” and other publications, bridization. Lemon is thought to be a hybrid resulting list ‘Eureka’, ‘Lisbon’, ‘Villa Franca’, and ‘Sicily’ as from a cross between citron and sour orange. Sour orange some of the varieties available at that time. The rough is in turn thought to be hybrid between pummelo and ‘Jambiri’ came as a rootstock in the 1920s and started mandarin. Subsequent mutations in lemon have led to the to produce prolifically by 1934. ‘Ponderosa’ and its many different types found worldwide. Lemon is known seedling ‘American Wonder’ and a sweet lemon were as limone (Italy), zitrone (Germany), limon (Spanish), all mentioned by 1934. limao (Portuguese); citron (French), and citroen (Dutch). Often called “local lemon,” ‘Rangpur’ and ‘Kona’ Lemon is believed to have originated in northern are very sour orange-colored limes. The ‘Rangpur’ lime India and Burma. The Romans were likely acquainted came to Hawai‘i as a rootstock of a grafted citrus plant, with lemons, sour oranges, and citron, but abandoned but the grafted variety died and the ‘Rangpur’ rootstock 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 co- operation with the U.S. Department of Agriculture, under the Director/Dean, Cooperative Extension Service/CTAHR, University of Hawai‘i at Mānoa, Honolulu, Hawai‘i 96822. Copyright 2011, University of Hawai‘i. For reproduction and use permission, contact the CTAHR Office of Communication Services, [email protected], 808-956-7036. The university is an equal opportunity/affirmative action institution providing programs and services to the people of Hawai‘i without regard to race, sex, gender identity and expression, age, religion, color, national origin, ancestry, disability, marital status, arrest and court record, sexual orientation, or status as a covered veteran. Find CTAHR publications at www.ctahr.hawaii.edu/freepubs. UH–CTAHR Lemons in Hawai‘i F_N-25 — June 2013 proliferated. Over the next 175 years these ‘Rangpur’ trees evolved into a lime with a puffy orange skin and very thorny branches also known as ‘Rangpur’. Its off- shoot, with tighter skin and very few thorns, is called the ‘Kona’ lime. These are in a group called Mandarin Limes. There is also a tropical subgenus of citrus called Papedas, some of which also came to Hawai‘i as root- stocks and now produce fruit here. ‘Ichang Papeda’ is often mistakenly called or sold as ‘Japanese Yuzu’. ‘Yuzu’, however, is another variety this subgenus, along with ‘Suidachi’, ‘Yuko’, ‘Kabosu’, ‘Khasi’, ‘Melanesian’, ‘Kalpi’, and the popular ‘Kaffir’ lime. Culinary and Other Uses ‘Meyer’ (Citrus x meyeri) The histories of lemons and cooking have been inter- Frank N. Meyer, who was sent to China by the twined since the beginning of recorded history. Recipes USDA’s David Fairchild, first found this lemon on a from ancient Greece, China, Persia, and India show fruit-hunting trip. Of the more than 2,500 species of the fruit was in demand, although it was not widely plants Meyer introduced into the U.S., this is the only cultivated. Originally used both in sweets, with copious plant that bears his name. This lemon has dramati- amounts of sugar, and in savories, the fruit began to be cally increased in popularity over the past 20 years, used by early cooks in a number of other popular dishes. in part due to Alice Waters and Martha Stewart It was added to couscous, dried and used in soups and featuring them in their cooking and shows. Meyer stews, and later in history, made into alcoholic drinks like lemon produces very well in warmer climates like lemoncillo. Lemon and lime pickles have been popular Hawai‘i when other lemons may struggle with the in India for more than a thousand years. Oil from lemon heat. The improved ‘Meyer’ lemon is a selection that peel is used in many products, from aromatherapy oils to was found in the 1950s and released in 1975 as an furniture polish. Other uses include mouthwash, disinfec- improved version that is resistant to Citrus Tristeza tant, and, mixed with water, heartburn relief. The Romans Virus. Ever increasing in popularity, ‘Meyer’ lemon used it as an insect repellent and to freshen clothes. is sometimes referred to as the sweetheart citrus. Cultivars and Varieties Found in Hawai‘i ‘Sweet Lemon’ (C. x limetta) There are hundreds of lemon varieties around the world; Called sweet lemons or, to a lesser extent, sweet however, many have not made their way to Hawai‘i. limes, these fruit are found in some areas in Hawai‘i. The most common lemons found in the Island are the “Sweet” is somewhat of a misnomer, as the fruit is following: generally insipid, with only a very slight taste. A number of varieties were introduced from India and ‘Kalpi’ (Citrus x webberii) later Brazil and Mexico, but they never achieved ‘Kalpi’ is one of the most common lemons in any commercial value. The fruit is not without fans, Hawai‘i. It is a natural hybrid found in the Philippines though, and there are a few named cultivars. that is presumed to have arrived with Filipino im- migrants. The name comes from the Bicol region of ‘Jambiri’ (Citrus x jambhiri) southern Luzon. These trees are found all over the The rough-skinned lemon, originally from North state and are very prolific. They are often confused East India, was commonly used as a rootstock for with small Italian lemons, very recent imports, and citrus coming to Hawai‘i. Those grafts died off and the larger rough-skinned ‘Jambiri’ lemon. ‘Kalpi’ is the tree became a popular backyard tree. Recent sometimes called Malayan lemon. molecular markers studies showed that it is a cross 2 UH–CTAHR Lemons in Hawai‘i F_N-25 — June 2013 ‘Eureka’ (Citrus x limon) The first ‘Eureka’ originated from seed in 1858 in Los Angeles and was propagated in 1877 by Thomas Garey, who called it ‘Garey’s Eureka’. Popularity rapidly increased, in part due to the tree’s being virtually thornless. The University of California lists 14 types of ‘Eureka’ lemons based on origin. Hawai‘i seems to have a few of these ‘Eureka’ types, includ- ing ‘Old Line’, ‘Frost Nucellar’, ‘Allen-Newman’, and the variegated pink-fleshed ‘Eureka’. The pink came from a shoot from a regular ‘Eureka’ prior to 1931 when budwood was distributed. ‘Pink Lemonade Eureka’ has become very popular in Hawai‘i over the past 20 years. between mandarin and citron. The tree is somewhat ‘Lisbon’ (Citrus x limon) resistant to a host of pathogens and extremely resis- ‘Lisbon’ is perhaps the most popular commercial tant to leaf spot but sensitive to Phytophthora and lemon next to ‘Eureka’, although its relationship to waterlogged roots. It is tolerant to both cold and the Hawai‘i has always been marginal as it produces hot Hawai‘i climate. It’s unclear if the fruit arrived much better in cooler areas. The trees are more in Hawai‘i with Don Francisco de Paula Marin in cold tolerant and most productive in California. the early 1800s or later with the first Portuguese im- Thick foliage better protects fruit from the sun. The migrants. The Spaniards are credited with bringing thorns are considerable. Yield is about 25% greater the fruit to Florida and the New World. There are a than ‘Eureka’. There is some disagreement as to the number of named cultivars, such as ‘Estes’, ‘Milam’, origin of ‘Lisbon’. What is known is that seeds were ‘McKillop’, ‘Nelspruit 15’, and ‘Lockyer’, although sent from Portugal to Australia in 1924. (The name it’s not known if these are in Hawai‘i. About 98% ‘Lisbon’ is not used for the lemon in Portugal.) It of the seeds planted are true to type, and the tree was listed in nursery catalogs as early as 1843.