By: Heather Rhoades
For a citrus grower, nothing can be more frustrating than waiting all season for a lemon, lime, orange, or other citrus fruit to ripen only to discover that the inside of the fruit has a thick peel with more rind than pulp. A citrus tree can look healthy and get all the water it needs, and this can still happen, but you can fix it and make sure that your citrus fruits never end up with a thick rind again.
Very simply, a thick peel on any kind of citrus fruit is caused by a nutrient imbalance. The thick rind is caused by either too much nitrogen or too little phosphorus. Technically, these two issues are one and the same, as too much nitrogen will affect how much phosphorus a plant will take up, thus causing a phosphorus deficiency.
Nitrogen and phosphorus are a citrus grower’s best friend. Nitrogen is responsible for foliage growth and will help the tree look lush, green, and be able to take in energy from the sun. Phosphorus helps the plant to form flowers and fruit. When these two nutrients are in balance, the tree looks beautiful and the fruits are perfect.
But when the two are out of balance, it will cause problems. A citrus tree growing in soil that has too much nitrogen will look very healthy, except for the fact that it will have very few, if any blossoms. If it does produce blossoms, the fruit themselves will be dry, with little or no pulp inside, and a bitter, thick rind.
A phosphorus deficiency will cause almost the same results, but depending on the levels of nitrogen, the tree may not look as lush. Regardless, the rinds on citrus fruits from citrus trees affected by too little phosphorus will be thick and the fruit inedible.
The easiest way to fix both too much nitrogen and too little phosphorus is to add phosphorus to the soil. This can be done with a phosphorus rich fertilizer or, if you are looking for an organic phosphorus fertilizer, bone meal and rock phosphate, which are both rich in phosphorus.
Thick rinds on citrus fruit does not just happen; there is a reason for thick peels on lemons, limes, oranges, and other citrus fruits. You can fix this problem so that you never again have to experience the disappointment of waiting so long for a fruit you can’t eat.
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Read more about Citrus Trees
Lemons are a type of yellow-skinned citrus fruits that grow on the lemon tree. All types of lemons are known for their acidic, sour taste with some varieties being sweeter than others. There are actually only a few varieties of lemons that are classed as “true” lemons. Many kinds of lemons are actually hybrids of true lemons and other types of citrus fruits.
The botanical name for lemon species is Citrus limon. Thought to have originated in South Asia, lemons are now a popular citrus fruit used all over the world. Lemon juice is also a rich source of vitamin C and the yellow peel contains lemon oil used to make essential oil.
Some of the most popular types of true lemons are Lisbon lemons and Eureka lemons. Although the majority of lemons have yellow juicy flesh, some types of lemons have pink flesh and are referred to as pink lemons.
In this article, you will learn about different varieties of lemons. From big lemons such as varieties that grow in India to smaller hybrid lemons such as the Meyer variety.
The government mandates some sort of treatment for any citrus moving interstate. There are options to use hydrogen peroxide, but I certainly didn’t see that listed – which wouldn’t even have to be rinsed, I’m sure! – on the boxes.
I just keep thinking about those lemon wedges floating around in my water all day, soaking off all this crap into my drink and my body. I picture my little guy gnawing on a lemon wedge because he thinks it’s funny.
And in a restaurant, where I love to get lemons too, how well do you think they’re washed before they’re cut (if at all)?
Last week, Redlands citizens were out in full force to show support to the Inland Orange Conservancy’s eighth annual Celebrate Citrus event.
During this fun event, guests of all ages were delighted by complimentary samples of local citrus, tours of local orange groves, live jazz music, creative art projects for kids and displays of citrus-themed art by local artists.
The event was fittingly held at Prospect Park, a preserved Redlands park that is completely surrounded by historical orange groves. In the past, Redlands was a fruit packing center surrounded by more than 15,000 acres of citrus groves.
What makes this fruit so appealing?
Citrus is affordable, lends flavor complexity to foods and often adds a missing flavor boost to any recipe.
Citrus offers tremendous nutritional value with loads of Vitamin C, folic acid, potassium, calcium and phosphorus for a healthy heart and kidneys.
The versatility of citrus is endless, and even makes for a great ingredient in delicious cocktails.
Not to mention the ubiquitous decorative group of lemons in a vase or bowl of oranges on a kitchen counter. The sweet aroma of spring blossoms is currently in the Redlands air, signifying the peak of citrus season.
As a chef who revels in utilizing locally grown ingredients, I feel privileged to live in an area where flavorful citrus is available all year round.
I love to juice oranges and lemons to make a great marinade, zest lemons to produce wonderful lemon bars, enjoy a squeeze a fresh lemon on fresh seafood and frequently start the day with a glass of fresh squeezed orange juice.
I love cooking with citrus of any type and almost every menu I design includes some application or some variety of citrus.
Citrus fruits include lemons, limes, grapefruits, tangerines, kumquats, oranges and several hybrids.
They are characterized by a thick rind, most of which is bitter white pith with a thin exterior layer of colored skin known as the zest.
The flesh of citrus fruit is segmented and juicy. Citrus fruits are acidic with a strong aroma their flavors vary from bitter to sweet.
Citrus fruits grow on trees and shrubs in tropical and subtropical climates worldwide.
All citrus fruits are fully ripened on the tree and will not ripen further after harvesting.
They should be refrigerated for longest storage.
When selecting citrus at the farmer’s market or grocery store, look for fruits that feel heavy and have thin, smooth skins.
Avoid those with large blemishes or moist spots.
Grapefruits are large and round with a yellow skin, thick rind and tart flesh.
They are an 18th-century hybrid of the orange.
Two varieties of grapefruit are widely available all year: white-fleshed or pink or ruby fleshed. White grapefruits produce the most juice although pink grapefruits are sweeter.
Fresh grapefruits are best when eaten raw or topped with brown sugar.
Kumquats are very small, oval-shaped, orange-colored fruits with a soft, sweet skin and slightly bitter flesh.
They can be eaten whole, either raw or preserved in syrup and may be used in jams and preserves.
Lemons, probably the most commonly used citrus fruits.
Lemons are oval-shaped, bright yellow fruits which are available all year.
Their strongly acidic flavor makes them unpleasant to eat raw but perfect for flavoring desserts and confections.
Lemon juice is also widely used in sauces, especially for fish, shellfish and poultry.
Lemon zest can be candied, used as a garnish or incorporated into a recipe for an extra intense flavor boost. Rubbing the skin of a lemon, or any other citrus fruit, with a sugar cube extracts much of the aromatic oil. The cube can then be crushed or dissolved to recipes calling for citrus flavor.
Limes are small fruits with skins ranging from yellow-green to dark green.
Limes are too tart to eat raw and are often substituted for lemons in prepared dishes.
They are also juiced in cocktails, curries, marinades and desserts.
Lime zest can be grated and used to give color and flavor to a variety of dishes.
Limes are available all year, but their peak season is during summer.
The key lime is a small tart lime variety native to South Florida and used to make key lime pie.
Oranges are round citrus fruit with a juicy, orange colored flesh and thin orange skin.
They can be either sweet or bitter.
Valencia oranges and navel oranges are the most popular oranges.
They can be juiced for beverages or sauces, and the flesh may be eaten raw, added to salads, cooked in desserts or used as a garnish.
The zest may be grated or julienned for sauces or garnish.
Sweet oranges are available all year. Their peak season is from December to April.
Blood oranges are also sweet but are small, with a rough, reddish skin. Their flesh is streaked with a blood-red color. Blood oranges are available primarily during the winter months and are eaten raw, juiced or used in salads or sauces.
When selecting sweet oranges, look for fruits that feel plump and heavy, with unblemished skin.
The color of the skin depends on weather conditions, a green rind does not affect the flavor of the flesh.
Bitter oranges include the Seville and bergamot. They are used primarily for the essential oils found in their zest. Oil of bergamot gives Earl Grey tea its distinctive flavor oil of Seville is essential to curacao, Grand Marnier and orange flower water. Seville oranges are also used in marinades and sauces for meats and poultry.
Tangerines, sometimes referred to as mandarins, are small and dark orange.
Their rind is loose and easily removed to reveal sweet, juicy, aromatic segments.
Tangerines are most often eaten fresh and uncooked but are available canned as mandarin oranges.
Tangelos are a hybrid of tangerines and grapefruits. They are the size of medium oranges they have a bulbous stem end and few to no seeds.
See you at all three Redlands farmer’s markets. Happy farm cooking to you and yours!
Citrus. I love them. Lemons, limes, mandarins, oranges, grapefruit, kumquats. I grow the lot of them. Right now my blood orange is covered in flowers and the scent wafting on the air is divine.
The lemons and limes are prolific this year, and the kumquats are at their best ever too.
But pests, diseases and nutrient deficiencies are common among citrus. If they're not given enough attention, they often succumb to all manner of disorders. A little bit of care goes a long way with citrus.
Above everything else, make sure you establish a regular feeding regime. Citrus are heavy feeders, and without fertilisers they'll likely end up with yellowing leaves – a sign of nutrient deficiency. Weaker plants also attract bugs, such as aphids, scale, mealy bugs and white fly.
Large infestations will weaken the plant further and reduce the size of the fruit. Sap-sucking pests are also responsible for sooty mould. Deal to pests as soon as they appear to prevent a rapid build up in the warmer weather.
Then start feeding. Little and often is best. Citrus in the ground are best fed with a specialist citrus fertiliser every six weeks from September to March. Citrus in containers can be given a slow-release fertiliser in September (if you missed the boat you can do it now) and again in summer, with a monthly application of liquid fertiliser.
Watering is necessary too. A lack of water can cause fruit drop or little or no juice in your fruit, so give plants a good soaking every couple of days. Apply a layer of mulch to conserve moisture in the soil and to keep down weeds, which compete for moisture and nutrients. Keep other plants away from the base of your trees – again, these will just compete for moisture and nutrients.
Make sure your soil is free-draining though, as waterlogging can be detrimental. The symptoms are easy to spot. You'll notice leaves and shoots begin to wilt. If that's the case, replanting may be necessary.
Thick skins? It could be a phosphorus deficiency. Phosphorus is the nutrient most directly affected by soil pH. Where soils are overly acidic, phosphorus availability is reduced. Feed with a citrus fertiliser regularly, as above.
But if you've ruled out a phosphorus deficiency, blame it on the weather – or the age of your tree. In cooler regions the skins of your citrus are much thicker than in areas with milder winters, and that's especially true of oranges. Sometimes the fruit at the back or shadier part of the tree are thicker skinned than those in the direct line of the sun. Younger citrus trees, while still maturing, often produce thicker skinned fruit too.
Lack of juice may be an indicator of too much nitrogen – switch to a citrus fertiliser, or cut back on the feeding.
Lack of fruit? Citrus trees are self-fertile, so lack of fruit is probably because of insufficient food or water.
Other than the occasional light trim, citrus trees typically don't need pruning, unless it's to shape your tree or prune out scraggly branches. Sometimes the branches of mature trees need thinning to increase air flow and allow more sunlight into the centre of the tree, which helps to reduce the risk of diseases.
If you have a mature tree that needs shaping, do it after the last fruit has been harvested. Citrus trees can be cut back fairly hard, though you're unlikely to get any fruit the following season. Cover the cuts with a pruning paste to prevent borer from entering.
While you're at it, prune neighbouring trees too if they're shading your citrus. If your fruit has black marks, it might be brown spot – a fungal disease. Eventually the fruit will drop off. Leaves may also be affected. Copper fungicides are used to control this disease. Wait until you get a dry spell before spraying your trees.
It's not all bad though. Give your citrus trees a little attention and they'll produce healthy foliage and an abundance of fruit.
A Distiller’s Guide to Mastering the Citrus Flavor Trifecta
How can a single fruit provide three contrasting flavors, extractable separately or in combination? Easily enough when it is a citrus fruit, and those flavors are held in discrete, divisible layers.
Lemons descend from a noble, versatile family of fruits. Its peel characterizes limoncello, its pith adds to the bitterness of a bitter lemon cocktail, and its juice endows a whiskey sour with acidity.
And yet generally speaking these fruits are constructed rather simply. With a couple of exceptions — notably finger limes and Buddha’s hand — citrus fruits have a juice-filled core surrounded by a cushioning layer of white pith and an exterior layer of aromatic peel. As well as working as solo notes, citrus fruits are nearly indispensible for making gin and vermouth in combination with a variety of other herbs, spices and fruits. Many gins incorporate grapefruit peel, and vermouths utilize the richness of dried orange peel. Citrus also combine well, notably in Seedlip Grove 42 that layers bitter orange, blood orange, mandarin and lemon.
Citrus fruit crops are some of the most widely cultivated in the world. Humans have been enjoying their taste and selectively breeding them for thousands of years. Combined with a propensity for hybridizing, a vast diversity of cultivated citrus has expanded the forms, colors and flavors of citrus far beyond the 10 wild species they are all descended from. Wild citrus originated in the southeast foothills of the Himalayas, diversified and moved into Australia. Commercial crops of citrus are grown outdoors in southern states: California, Florida, Arizona, Texas, South Carolina, Georgia, Alabama, Mississippi and Louisiana because most citrus trees have low tolerance for the cold temperatures they would be exposed to further north. However, citrus are amenable to being grown in pots and kept indoors over winter, and because their peel in particular offers a concentration of aroma, one or two trees can furnish a distiller with enough raw material for regular batches of citrus-infused spirit. In the cold winters of Massachusetts, Berkshire Mountain Distillers have a couple of potted citrus trees that are brought into the distillery to protect them from frost.
Mandarins (Citrus reticulata) are familiar on supermarket shelves. However, there is a use of mandarin that is novel to the US spirits market but well embedded in aromatic products like shampoos and essential oils. Unripe mandarins that are still green and not orange have superlative aroma, and this is made use of in beverages in the Mediterranean. In southwest Turkey, people take an early crop of green mandarins and store them in their freezers to put in drinks throughout the year. In Sicily, the green peel is macerated in spirit for three weeks and then combined with sugar syrup to make a liqueur. In its unripe green state, mandarin peel has a freshness that balances the more familiar aroma of ripe mandarins, making it less saccharine.
Key limes (Citrus x aurantifolia) are the eponymous fruit of the Florida Keys, although most key limes on the market are supplied by Mexico. After a hurricane in 1935 destroyed the last commercial crop trees and the increase in accessibility and land value following the completion of the overseas highway linking the Florida Keys to the mainland, the only key limes left in the Florida Keys are in gardens. In contrast to Persian limes (Citrus latifolia), they are ripe when yellow, yield more acidic juice, contain less pith and have more aromatic peel. Falernum is the perfect product to showcase key limes, as it uses both peel and juice 24–48 hours is long enough to macerate the lime peel and spices, and a short enough time to leave the juice inside the peeled limes until the infused rum, sugar and juice are combined to make the finished falernum.
Citrus have flavored distilled products for hundreds of years, but recent developments in cultivars, crops grown and distribution in the US have increased the distilling repertoire. Meyer lemons (Citrus x meyeri) blend characteristics from their parentage of lemon and orange. Their peel is a particularly desirable combination of lemon with warmer notes of orange. They aren’t widely available as a commercial crop because their soft skin is easily damaged, which makes them more difficult to transport. But they are popular on a local scale. Initially introduced from China in 1908 as a cold-tolerant lemon, they were symptomless carriers of the tristeza virus that caused great damage to citrus crops. However, since virus-free clones were released in 1975, they have been regaining commercial use. Juicing Meyer lemons can be a quicker way of separating aromatic peel from juice than peeling them. Vapor infusion of the fresh peel is the ideal way to capture its taste in spirit.
Marketing and distribution networks are also more able to connect seasonal citrus with buyers. Buddha’s hand (Citrus medica var. sarcodactylis) has had some Halloween rebranding with the name goblin’s fingers. It is a cultivar of etrog or cedro (Citrus medica), which are characterized by particularly thick pith. Buddha’s are divided into segments that resemble a hand. For distillers, Buddha’s hand presents two appealing characteristics. While the peel is citrus-scented, it also has a lavender-floral note, to the extent that one left out in a room perfumes the air enough for people to ask what it is. They contain no flesh or seeds: Inside the skin, the fruit is entirely pith. With the absence of seeds, they are replicated as cuttings. Their pith does not carry as much bitterness as the pith of many other citrus. Consequently the fruits are easily prepared for making use of the aroma of their peel because there is are no need to separate peel from pith, and no juice to contend with. The entire fruit can be cut and left to macerate in spirit prior to distillation. If macerated after distillation, the spirit will retain a light yellow tint. An important handling note is that citrus pith is rich in pectin. This is removed by distillation but if citrus peel is added after distillation, pectin present in the final product can cause a pectin haze, particularly when the spirit or liqueur is chilled. Another method of reducing pectin content is freezing. Citrus retain flavor well when frozen, but pectin is degraded by freezing.
Finger limes (Citrus australasica) are a new crop for the US that entered the market as specialty produce sold to chefs and restaurants. As production increases, they are more readily available. Still found as a wild plant in Australia as well as being cultivated, they are used in several Australian gins. These are citrus without pith. Their incredibly fragrant peels encase a cluster of round juice-filled vesicles, which look like pink, clear or green caviar. Shanley Farms, in California, is one of the main growers of finger limes for the US market. They sell them whole and also sell the juice-filled vesicles as citrus pearls. Lauren Taylor of Shanley Farms said, “At this time, the peel of the finger lime is not part of the show. Although a by-product of the main event — the citrus pearls — the peel will eventually be sold to press and extract the oil.” Potentially an opportunity for a distiller to access a supply of this peel that in addition to being aromatic is a by-product. This is congruent with increasing awareness in the drinks industry of reducing waste. While the finger-lime season runs from January to June, like all citrus, the peel retains flavor and aroma when dried.
Yuzu (Citrus x junos) is another citrus that was not a common find in the US because it doesn’t have the sweet juice that fits well in a fruit section, although yuzu juice is indispensible in Japanese cuisine. Combining intense sourness with a blossomy note, the juice is suited to addition post-distillation to retain its acidity. Additionally, yuzu peel is widely used as a condiment in Japanese cuisine in its own right and as a component of shichimi and yuzu kosho. In both of these spice blends, yuzu peel lightens the fierceness of chili and pepper. Gins made in Japan and Japanese-inspired gins are making use of yuzu peel. It is convenient as a dried ingredient that is easily stored. Furthermore, yuzu trees are considered cold-hardy down to 10°F, so they can be grown outdoors further north than most citrus. Yuzu peel is best used in short maceration or vapor distillation.
When looking to use citrus, it’s worth considering varieties beyond grapefruit, orange, lemon and lime. Some citrus fruits, such as finger limes and Buddha’s hand, are seasonal while others, for example key limes, are connected to place. In all cases, it is worth remembering that these are fruits that can offer three layers of organoleptic experience when their peel, pith and juice are considered independently.
A patent for preserving lime juice with sulphur dioxide launched a Caribbean “Lime Juice Cordial” industry in the 1860s. Limes were crushed between rollers at sugar cane mills. Juice was decanted into wooden vats and allowed to settle. After two weeks, clear juice was drawn off, sweetened with sugar, treated with sulphur dioxide and sealed in casks. Current production technique include adding calcium carbonate to shorten settling time. The juice is sweetened with cane syrup and pasteurized before bottling.