Limes enhance your garden and your food

In 1971, Harry Nilsson wrote a song about combining lime and coconut. “Put the Lime in the Coconut” made the hit parade that year and it is still a recognizable ditty. With coconut water readily available and limes currently fruiting in abundance, you might want to give the combo a try to see if you want to plant some limes to flavor your coconut or to use in recipes. Cocktails, soups, salads, dressings and desserts can all be enhanced with the unique flavor of limes.

It is the distinctive flavor of this tart member of the citrus family that recommends its use. The ovoid fruit of the lime tree is green when ripe and usually smaller than a lemon, less than 3 inches long. Limes are often used interchangeably with lemons, but are usually less sour and have a fresh flavor that distinguishes them from other citrus.

Limes likely originated in islands of Indonesia or the nearby Asian mainland. They were first cultivated in areas like Persia and Babylonia (now Iran and Iraq) and were introduced to India and later reached Africa around 1,000 A.D. Returning crusaders brought limes to western Mediterranean countries in the 12th and 13th centuries and Columbus took seeds to the West Indies in 1493. Lime cultivation quickly spread to Mexico and Florida and seeds probably arrived in Hawaii with some of the early missionaries.

During the 19th century when the British navy ruled the seas, scurvy (a disease caused by a lack of vitamin C) plagued sailors in the fleet on long journeys. It was discovered that limes contained enough of the vitamin to prevent scurvy, and ships began carrying a full load of the green acidic fruit, which was readily available in their Caribbean colonies. Today, the nickname “limey” is still sometimes used to refer to English sailors.

Although several lime cultivars exist, only four are commonly available in Hawaii. The Tahitian lime (Citrus x latifolia) sometimes known as Persian or Bearss lime, is probably the best choice since it seems resistant to diseases. The Key lime (Citrus aurantifolia), also known as Mexican lime or bartender’s lime, is less available today, but can be found in many backyards and citrus orchards around the state. The Kaffir lime (Citrus hystrix) is quite different in flavor, less juicy and has a bumpy skin but is a popular variety as the leaves are called for in many Asian recipes. Rangpur (known locally as Kona) lime is not actually a lime. It is a botanical cross between a mandarin orange and a lemon (Citrus x linonia). It has a flavor more like a lemon, but can be used as a substitute for limes. Many of these lime cultivars have thorns, though some thornless varieties can be found.

Tahitian limes are an excellent candidate for a lanai container, or a small backyard garden as well as part of an orchard. Their disease resistance makes them a high recommendation, as is the medium size of the tree and its frequently heavy production rate. The trees, which can reach to 20 to 25 feet in height when mature, are similar to lemon trees with larger, darker green leaves than their Mexican cousins. Tahitian limes are vigorous trees that produce fragrant flowers followed by a thick skinned fruit nearly 10 months of the year. When ripe, the green fruit will begin to turn slightly yellow and be full of juice without seeds.

Mexican limes have recently become vulnerable to several diseases that make it a less desirable choice for commercial growing in Hawaii and fewer nurseries carry this variety. Their fruit is usually larger than the Tahitians and may contain more juice, though the flavor is very similar.

Kaffir limes grow on smaller trees with a compound leaf unlike that of other limes. The trees produce flushes of soft, purple new leaves throughout the year that mature to a glossy, dark green. The aromatic leaves, as well as the tree’s small size, make it an excellent candidate for lanai containers, especially when placed near the kitchen. Kaffir leaves are an important ingredient in many Thai recipes as well as Asian stews, soups and curries. The Kaffir lime fruit is small with a wrinkled skin that contains pungent oil. Though the pulp has a lime-like flavor, the fruit is drier and seedier than its cousins. Zest made from the skin is often added to dishes using Kaffir leaves to enhance the flavor.

Though Kona limes have been used historically as strong citrus root stock, the fruit has recently become popular with chefs and consumers for its sour flavor and deep orange coloring. The mandarin cross has not only leant it the bright color but also a loose skin that is easy to peel. Originally from the region around the Rangpur province of Bangladesh, northeast of India, the Rangpur lime arrived in Kona around 1880. It has undergone slight genetic variations in its new home that qualify it for the new name, Kona lime.

Like most members of the citrus family, limes prefer growing conditions of full sun with soil that drains well. Though not highly tolerant of salt, wind or drought conditions, they are very adaptable plants that can be grown from sea level to about 3,000 feet in elevation. They will not tolerate freezing temperatures or waterlogged roots. Mulching along with applications of fertilizers made especially for citrus should keep limes happy and healthy. Watch for chlorosis (yellowing) on the leaves, which is a good indication of soil fertility issues. This can be addressed by adjusting the pH of the soil to slightly acid, which will allow the plants to adequately absorb nitrogen and zinc.

Pruning citrus trees can help keep them healthy with adequate air flow moving through the foliage. Be sure to remove dead, diseased and crossing branches regularly while eliminating any sprouts that may grow below the graft from the rootstock.

Propagation of most limes requires grafting or layering as they do not always grow true to seed. The Kona lime, however, can be dependably grown from seed. For dependable results asexual propagation techniques work best for other varieties.

Citrus seedlings will usually produce fruit within four years. Grafted limes will often produce some fruit in their second year. First-year fruit should always be removed to allow the tree to put its energy into root and stem development when it is young.

Citrus trees attract many insects and diseases here in Hawaii but most are easy to treat.

Though citrus leaf miner can be unsightly, it can usually be controlled if leaves containing the pest are removed and destroyed early in the infestation. Limes are susceptible to several different root rots that can be prevented if watering is limited and the soil drains well. Aphids and scale can be problematic and cause sooty mold to appear. Controlling ants and spraying neem oil mixed with Safer brand soap on the insects can be helpful.

The citrus tristeza virus is a problem that many growers have experienced. The disease is fatal and starts with leaf drop and limb death, which proceeds slowly through the entire plant. Studies have shown the Kona lime to be the most resistant to this disease, with the Mexican lime being the most vulnerable.

Lime aficionados definitely prefer their taste to that of lemons. Many cocktail recipes specifically call for limes over lemons. Of course, Key lime pie must use limes and the flavor of the Kaffir lime leaf and zest is found nowhere else. Lime and coconut water make a delicious drink and adding lime to guacamole or other dips adds a different flavor and zing.

Many local nurseries carry at least one lime variety. Choose one that suits your needs and flavor preference and you’ll be enjoying limes for years to come.

Diana Duff is a local organic farmer as well as a plant advisor and consultant.