Tropical Fruit – A Tasty Survey, Part IX

This week we continue our survey of interesting tropical fruit species that can be grown in southern Florida.

Nopal Cactus (Opuntia cochenillifera)

You might ask why Opuntia is included in this series. While it may be hard to envision this genus as a conventional tree, and while its fruit really functions as a vegetable, and while many of its species are subtropical and even temperate, no one should doubt that it belongs in this space, for it is a very valuable food source.

Opuntia is a cactus represented by more than 150 species distributed throughout the Americas, extending as far north as British Columbia. The plants bear flat, fleshy structures commonly mistaken for leaves. But because leaves are a fragile commodity in dry climates, the dominant architectural feature of Opuntias is their stems, or pads, which, like their fruit, are generously covered in spines. Some species reach over 15 ft. in height. There is substantial evidence that Opuntias have adapted to specific elements within their environment: Of the six species native to the Galapagos Islands, the taller-growing ones are generally found on the islands where there are tortoises, while short or prostrate species are generally associated with those islands devoid of tortoises. By that means of adaptation, the giant tortoises for which the islands are famed get to eat nopal—by having it served to them rather than devouring the plant into extinction.

Nopales are eaten by humans either raw or cooked; it’s easy enough to cut around the vicious spines. This genus is particularly important in Mexico, where over 100 species of nopal are endemic. The nation devotes close to 7.5 million acres (3 million hectares) to the production of Opuntia for consumption by both humans and livestock. Sources range from the wild to family gardens or farms to commercial plantations.

One of the most popular dishes is huevos con nopales, in which pieces or slices of the pads are scrambled with eggs. Often the sweeter-tasting fruits, known as nopalitos, prickly pear, or tuna, are used instead of the pads. Nopales are often mixed with meat, too.

Nopal is a healthful food, providing a significant source of manganese, vitamins A and C, and magnesium. It also ranks among the lowest-calorie vegetables.

Allspice (Pimenta dioica) and Bay Rum (Pimenta racemosa)

The genus Pimenta comprises14 flowering species, among which are some of the most interesting and desirable aromatic trees in the world. But it’s all a mistake . . . a big mistake. Spanish explorers poking around Mexico in the 16th century found an attractive medium-sized tree whose berry-like fruits resembled black pepper, so they called it pimienta, the Spanish word for pepper. That error has become preserved in the genus name. We concentrate below on two of the most significant representatives of Pimenta.

Pimenta dioica, the specific plant mistaken for a new source of black pepper, is better-known to most people as the allspice tree or, in another long-perpetuated error, the Jamaican pepper. The name allspice was bestowed on it by the English around 1621 because they considered its complex taste a combination of clove, cinnamon and nutmeg. The first recorded instance of the importation of the spice into Europe came in 1601.

This beautiful tree reaches 30-40 ft. high and features aromatic, leathery, glossy, oblong 4-8 in. leaves. The bark, whitish-gray in color, peels away in thin sheets. The tree produces clusters of white flowers which are followed by berry-shaped fruits that mature purple-black. However, in the commercial production of allspice, the fruit is picked green and dried in the sun. The major volatile oil responsible for this species’ fame is eugenol.

The allspice tree is native to the Greater Antilles (Jamaica, Hispaniola, Puerto Rico and Cuba), southern Mexico and Central America. While the tree is now cultivated in many tropical areas of the world, it is apparently the only spice processed commercially solely in the New World, particularly Mexico, Honduras, Jamaica, Trinidad and Cuba. Jamaica was the leading exporter of allspice, at least until the 1990s, but there is now some indication that Mexico has superseded it, and Honduras and Guatemala are becoming major exporters.

Once P. dioica is established, it withstands drought and even has some cold tolerance — 26-28°. It can be grown nicely as a container specimen, as well as in the ground, and performs best in full sun. While the allspice tree may not flower and fruit dependably outside native areas, it is still quite desirable; even the bark is aromatic.

Most folks know that the spice is used in a variety of condiments, and also in pies, cakes and candies. But eugenol is also an important constituent of cosmetics and perfumes. And it may surprise some to learn that allspice is even found in the liqueurs Benedictine and Chartreuse, as well as in Northern European food staples such as pickled fish and sausages. Eugenol also has medicinal applications as an aid to digestion and an anesthetic for toothaches. This would appear to suggest that the pies, cakes and candies which contain allspice must also cure toothaches. Could there be a more perfect food?

The second tree, Pimenta racemosa, better-known as Bay Rum or West Indian Bay Tree, is variable in height, maturing in the 12-40 ft. range, but generally shorter than P. dioica. It is native to the West Indies and possibly northern South America. The tree bears attractive, small white flowers which give way to black ovoid fruits. This species has about the same cultural requirements as the allspice tree, but is several degrees less cold-hardy.

Bay rum is distilled from the berry-like fruits of P. racemosa, but this essential oil is not used in beverages because in that concentration ingestion is toxic. Instead, it is used as a constituent of colognes, perfumes and soaps. On the other hand, the leaves of this species are fine for consumption as a syrup or herbal tea, or in cooking. Leaves are sold fresh or dried. Medicinally, bay rum has long been employed to treat sore muscles and various strains and sprains. Scientists later discovered that the essential bay oil contains a constituent possessing anti-bacterial properties. And even more recently, at least one study has characterized bay oil as a potent antioxidant.

Richard Lyons’ Nursery sells these desirable species in several sizes.

Tropical Fruit – A Tasty Survey, Part VIII

This week we resume our survey of interesting fruit trees that can be grown in southern Florida.

Persimmon (Diospyros kaki)

Chinese in origin, the persimmon (Diospyros kaki) is a wonderful fruit which unfortunately has had a reputation for doing poorly in southern Florida. Most of us think of persimmon as a California crop. After all, it was introduced there in the mid-19th century. However, its popularity has led to the creation of more than 2,000 cultivars, and finally Richard Lyons’ Nursery has come upon a hybrid that succeeds in our area.

Fittingly named Triumph, this very tasty cultivar will now allow growers in southern Florida to harvest a fruit—sometimes sold under the name Sharon—that is low in fats, high in dietary fiber, and possessed of anti-oxidant, anti-inflammatory and anti-hemorrhagic properties.

Persimmon trees are also ornamentally appealing, growing to a moderate size and featuring glossy green leaves. Triumph in particular grows at a very deliberate rate and will not overwhelm even small yards. When laden with fruit, the trees are particularly eye-catching. Triumph bears a tomato-shaped fruit that should be picked when mature—that is, fully-colored but still hard. Left to soften on the tree, the fruit will begin to attract hungry wildlife. The best practice is to leave picked fruit out at room temperature until it softens and its astringency has disappeared.

June Plum (Spondias dulcis)

Spondias dulcis has more names than an art thief on the run from Interpol: Pomme cythere in Trinidad and Tobago, cas mango in Cameroon and the Maldive Islands, juplón in Costa Rica, buah long long among the Chinese in Singapore, cajá manga in Brazil, kedondong in Indonesia and Malaysia, ambarella among the Sinhalese in Sri Lanka, golden plum in Belize, mangotín in Panama, and jobo indio in Venezuela. Closer to southern Florida, it goes by June plum in Jamaica and Bermuda. The last name gets the nod at our nursery.

In truth, S. dulcis is not a fugitive at all. It has lots of common names because of its multifaceted popularity as a fruit source. Originally native to Polynesia and Melanesia, the species’ reputation has led to its distribution throughout the tropics. It was introduced to Jamaica in 1782, and started to be grown there more widely ten or eleven years later when Captain William Bligh brought plants from Hawaii. In 1909 a source in Liberia sent seed to the USDA, but it did not catch on as a money crop in the US, possibly because its cold tolerance is just a few degrees below freezing.

The June plum is fairly fast-growing, maturing to the 30-40 ft. range in southern Florida, though more likely to grow 25 ft. taller in its native range. Pollination of its inconspicuous white flowers yields a hard green fruit which often falls off the tree and ripens to a yellow-golden color on the ground. Inside the fruit is a fibrous seed.

Eaten raw, June plum fruits are crunchy, featuring a pineapple-mango flavor with a bit of tartness. As they get further along in ripeness, they become softer. The fruit’s versatility has led to its being incorporated into a number of food dishes around the world. It is, for instance, made into jams and preserves and used to flavor stews, sauces and soups. It may be eaten with a shrimp paste or combined with chiles and other spices into a snack food. Elsewhere, the fruit is made into a drink in the company of ginger and sugar. It is also used in curries and, when dried, rendered into a spicy chutney.

But the story doesn’t end there. The fruits of S. dulcis are reputed to contain a wealth of qualities that promote good health. Among them are Vitamin A to maintain retinal sharpness and to improve wounds, Vitamin B1 and iron to prevent or treat anemia, calcium to fortify the cardiovascular system, sucrose to increase endurance, and antioxidants to counter free radicals. Leaves and bark of the June plum are also said to possess medicinal properties.

This interesting species can grow in alkaline or acidic soils and, so long as a sunny exposure and good drainage are provided, is not demanding. Finally, don’t let the name June plum mislead you; the species fruits almost all year.

Akee (Blighia sapida)

It’s not often that Captain Bligh is mentioned in Richard Lyons’ website, but this week you get a twofer: Bligh was the person responsible for transporting this very interesting tree to Kew Gardens from Jamaica in 1793, four years after the mutiny on the Bounty. Akee had been introduced to Jamaica earlier in the eighteenth century from its native tropical West Africa. As you might have guessed by now, a botanist named the tree for Bligh.

Blighia sapida, as a member of the family Sapindaceae, is related to lychee, rambutan and logan. It matures in the 30-ft. range in our region, with a fairly short trunk and a dense crown. When pruned appropriately, the tree stands up well to hurricanes. Akee (or ackee) produces fragrant white flowers, but it is the fruit of the tree that receives star billing. Mother Nature is often quite mischievous, and in the fruit of B.sapida she has created something both poisonous and edible. In fact, akee is Jamaica’s national fruit, and akee and salt fish is its national dish!

The key to unlocking akee’s charms is timing: Until the pear-shaped red-yellow fruit splits open, or yawns, all of its parts are poisonous. The open fruit reveals three large, shiny black seeds, each of which is partly embedded in a white-yellow pulp, the aril. When the fruit is fully ripe and still on the tree, the arilli are edible. Featuring the consistency and appearance of scrambled egg, they may be eaten fresh or cooked. One simple, tasty preparation is to sauté the arilli in butter.

B. sapida is best grown in full sun on a well-drained site. It is quite tolerant of our limestone soils, and a mature tree can handle temperatures into the mid-20s for brief periods. The tree has no major pests or diseases.

Richard Lyons’ Nursery carries these species in various sizes.



Plants Toxic to Dogs and Cats—Redux

The U.S. is a nation of pet owners, and most of us feel a duty to protect those pets from various threats. Among the risks are toxins found in certain plants. Richard Lyons’ Nursery has addressed this subject before—just 18 months ago—but considers it important enough to merit repeating. Here is an expanded version of that column.

Many of us reside in southern Florida because of the wonderful winter climate that permits us not only to enjoy the great outdoors without bundling up, but also to cultivate thousands of tropical and temperate plants. However, as the old saying goes, there is no good unalloyed, and not every plant is benign. If you own a dog or cat, it behooves you to become familiar with the species that may harm your pet. Below you will find a list of a few of the plants known to affect pet health adversely. (Due to space limitations, this survey pertains only to dogs and cats. Besides, if your pet is a woolly mammoth, it’s probably better off indoors in an air-conditioned room.)

Ricinus communis (Castor Bean): While this species is the source of castor oil, it also possesses a darker side: Its seeds contain the highly toxic substance ricin, which received great attention after 9/11 as a means of conducting chemical/biological warfare. Ingestion of just a few seeds by a dog or cat can set up a fatal chain of neurological events.

Abrus precatorius (Rosary Pea): This species is not only an invasive exotic, but also the source of abrin, a highly toxic compound that occurs naturally in the plant’s seeds. Fortunately, an ingested seed is relatively harmless so long as its coating is intact. But if the surface has been scratched, crushed or otherwise damaged, the result can be deadly to both pets and their owners. In fact, abrin is more toxic than ricin.

Aglaonema, Alocasia, Colocasia, Dieffenbachia, Monstera, Philodendron, Spathiphyllum, Syngonium: Dumbcane, the common name for Dieffenbachia, provides a hint of the harm that these and other aroid species can cause. Ingestion of the calcium oxalate crystals found in the leaves of these plants can cause swelling inside the mouth of your pet (and humans may find themselves unable to speak). Dogs and cats may experience intense burning and swelling, along with drooling and vomiting.

Nerium oleander (Oleander): This flowering shrub, better-known simply as oleander, is an Old World native that has achieved widespread distribution throughout milder climates in the United States. Its dicey constituents are known as cardiac glycosides, and while they have beneficial medical applications, in the concentrations found in all parts of this plant they can be toxic to dogs and cats. Symptoms include diarrhea, sweating, poor coordination, compromised breathing, tremors, and abnormal cardiac functions. Even inhalation of the smoke of oleander trimmings being burned can be toxic.

Aloe vera (Aloe vera): This popular plant is well-known for providing relief for burns through application of its gel, but what’s good in it can also harm pets. Among the many chemical constituents of Aloe vera are saponins, which have long been used in soapmaking. However, when ingested by dogs or cats, saponins can cause anorexia, depression, diarrhea, and tremors.

Cycads: This ancient family has a dual personality. Cycads are both a food source and a toxin. An edible flour can be made from the pith inside the trunks of these plants, but only following considerable processing.  Underprocessed flour, along with the seeds and leaves of cycads, are toxic to humans and their pets, and significant ingestion can lead to severe neurological disorders. Where dogs and cats specifically are concerned, the leaflets are low-risk, since they are generally quite stiff and often edged with spines. The bigger threat is from seeds. The risk to your animals can be reduced by removing the cones of female cycads before they release their seeds.

Lycopersicon spp. (Tomato): Few people think of the tomato as potentially harmful to domestic pets, but its leaves contain the chemical solanine, which can cause the following symptoms in cats and dogs: loss of appetite, central nervous system depression, slow heart rate, drowsiness, diarrhea, confusion, severe gastrointestinal upset, weakness, dilated pupils, and behavioral change.

Brunfelsia nitida (Lady of the Night): A relative of tomato, this popular shrub can be quite toxic, more likely to dogs than cats, in the form of gastrointestinal or central nervous system disorders. Though all parts of the plant have toxic properties, the greatest risk is from ingestion of the berries. In most cases, prompt treatment will lead to full recovery.

Vinca spp. (Periwinkle): Here’s another example of a plant containing chemical constituents—in this case vinca alkaloids—which do both good and harm. While the compounds are used to treat certain cancers in humans, they can also cause severe problems when ingested by small pets, including low blood pressure, diarrhea, depression, tremors, vomiting, seizures, coma, and even death.

Asclepias spp. (Milkweed): What’s good for the monarch butterfly is not necessarily good for your dog or cat. Milkweed ingestion can cause a variety of symptoms: seizures, vomiting, respiratory distress, dilated pupils, weak pulse, cardiac arrhythmias, liver or kidney failure, coma, and death. Not all species of milkweed—there are 21 in Florida alone—are equally toxic, but it’s best to keep your pets away from them.

Asparagus densiflorus cv. Sprengeri (Asparagus Fern): This ubiquitous ground cover contains sapogenins, which can cause a lot of mischief in cats and dogs. If your pet is regularly exposed to the leaves of the plant, allergic dermatitis may set up. More significantly, ingestion of the berries of this plant can result in gastric problems such as abdominal pain, vomiting, and/or diarrhea.

Crassula arborescens (Silver Jade Plant): Unlike other species discussed in this article, the toxin at work here is unknown, but the dog or cat that takes a liking to the plump leaves of this succulent plant may soon find itself experiencing a bout of retching or nausea.

Allium cepa (Onion): We know that the onion is a heart-healthy vegetable for humans, but much less well-known is the fact that it may cause misery in pets, particularly cats. The culprit is N-propyl disulfide, which can cause a broad spectrum of symptoms, including gastrointestinal upset, breakdown of red blood cells, vomiting, weakness, panting, elevated heart rate, and blood in the urine.

Gloriosa superba (Gloriosa Lily): This herbaceous perennial produces beautiful, delicate flowers after lying dormant during the dry season. But it also produces colchicine-related alkaloids throughout the plant, and they can cause salivation, diarrhea, vomiting, kidney failure, shock, liver damage, and bone marrow suppression.

Kalanchoe spp. (Mother of Millions): These succulent plants tend to produce offspring, often in maddening numbers, interestingly at the margins of leaves. Most flower during the winter. The constituent which can affect your cat or dog is bufodienolides, which can cause diarrhea, vomiting and, occasionally, abnormal heart rhythm.

Citrus aurantifolia (Key Lime) and Citrus latifolia (Tahiti or Persian Lime): Ingestion of both these types of limes can cause distress in dogs and cats, including depression, vomiting and diarrhea. Furthermore, as in humans, exposure in sunlight to psoralens, oils found in the rinds of these fruits, can set up a very strong allergic response. (The risk of photosensitive reactions explains why limes grown commercially in Florida came to be packed within covered structures.)

Brugmansia spp. (Angel’s Trumpet): The seven species in this genus produce showy, pendant, trumpet-shaped flowers, but all plant parts contain toxic levels of tropane alkaloids which are capable of causing fatal reactions upon ingestion. At the very least, pets (and humans) who swallow the leaves, seeds or flowers of Brugmansias can experience blurred vision, dilated pupils, constipation, high blood pressure, and muscle weakness.

This list should in no way be considered all-inclusive; you are urged to research the topic on your own for additional information. You may want to start with the following informative sites:


The foregoing brief survey of toxic species found in southern Florida is not meant to alarm plant enthusiasts who also own cats and dogs. On the contrary, it should reassure you that despite being surrounded by germplasm that contains toxic substances, your pets seldom find themselves compromised. What we hope is that on the rare occasions when your dog or cat does ingest part of a toxic plant, you will recognize symptoms at a very early stage and make a call to your veterinarian for advice.

Update on Avocado and Citrus

Over the past few years, Richard Lyons’ Nursery has reported from time to time on disease problems in avocado and citrus that have imperiled the future of both fruits as commercial crops in Florida. It is time for another update.

Avocados have been hit hard by laurel wilt, a disease spread by Xyleborus glabratus, the redbay ambrosia beetle. The insect, native to Asia, was first detected in Georgia in 2002, and has spread in all directions rapidly since then. Though the beetle’s primary interest is redbay trees, once it decimated those populations, it began to attack avocado, another member of the laurel family.  Originally, it was thought that the ambrosia beetle was the only beetle spreading the laurel wilt disease, but recently several other beetles have been identified in the spread of this fungus.

The quarterly magazine Modern Farmer recently reported that about 40,000 avocado trees have been lost in Florida. That is particularly ominous for Miami-Dade County, where traditionally 98% of the state’s commercial avocados have been grown.

Avocado trees are sitting ducks in the assault by laurel wilt. That’s because their root systems grow shallowly and radiate laterally. It means that in a commercial grove, where the root systems of trees touch—and, in fact, graft with—one another, a pathogen like the fungus that causes laurel wilt is able to spread through the plot fairly quickly. In addition, by the time a tree exhibits a physical manifestation of laurel wilt disease, such as the browning of leaves, it is too late to save the tree.

Accordingly, early detection of laurel wilt has come to be recognized as highly important to the effort to slow the spread of the disease. Research funded by the Florida Department of Agriculture and Consumer Services has led to the use of dogs trained to detect the scent of the laurel wilt fungus before an infected tree shows outward signs. First a drone is flown over an orchard to spot trees with browning canopies; those trees are removed, and the dogs are then released into the orchard to detect any trees in the early stages of infection. Those trees undergo a program of treatment to attempt to save them. However, the cost of identifying and treating diseased trees is high, so while detection via canine olfactory sensitivities is quite helpful, it nevertheless is best recognized as a mechanism that doesn’t stop the spread of laurel wilt disease, but, rather, slows it until a cure can be developed.

Meanwhile, the outlook for citrus in Florida, particularly the southern part of the state, is also tenuous. In recent decades, the family has encountered the one-two punch of citrus canker and citrus greening. The latter scourge, though more recent, is the more threatening, because it is much more likely to kill afflicted trees.

Citrus greening, also known as Huanglongbing (HLB), is caused by a bacterium that was discovered in southern Florida in August 2005 and has proved to be a formidable threat. Leaves of infected trees become chlorotic, or yellow; the visible symptoms of this chlorosis are typically referred to as “blotchy mottle.” In fact, that is probably the most reliable diagnostic symptom of citrus greening disease. The yellowing may show up in a single branch, particularly in a younger tree, and then spread throughout the plant in a year’s time. Developing fruits are misshapen and remain green instead of ripening, and their taste is rendered bitter. The disease, which, like citrus canker, is not harmful to humans, is incurable in plants, and most affected trees die within several years. The drop in orange production has been precipitous. The State of Florida last February lowered its prediction for the 2017-18 season to 45 million boxes; the high-water mark in orange production was 244 million boxes in 1997-98.

Researchers in citrus-growing regions around the world have been working earnestly for methods of cure or treatment of citrus greening. One proposal several years ago involved infusing an infected tree with antibiotics. But that required placing a cover or tent over the entire tree, a labor-intensive and expensive process. There doesn’t appear to be any recent writing on the subject.

In April 2018 it was reported that more traditional applications of bactericides—two brands of oxytetracycline and a streptomycin compound—had had variable results following three years of testing, and success appeared related to the number of annual doses. Other potential treatments have emerged in recent years. One is Benzbromarone, a drug developed to treat gout. Another is Zinkicide, a bactericide specifically created to work systemically within affected trees.

It must be emphasized that even if one or more of these chemicals makes it through the testing and regulatory processes to become commercially available to growers at reasonable prices, they are not cures for citrus greening. They are management techniques that might keep infected trees healthy enough to increase yields. A true cure for HLB does not yet appear on the horizon.

If all the foregoing obstacles weren’t enough, there is an additional challenge for backyard and commercial citrus growers in southern Florida—our alkaline soil. Upstate a number of desirable cultivars are grafted onto rootstocks that perform well in that region’s soils. Unfortunately, those rootstocks are incompatible with our limestone-based soils, and the fruits produced here are pithy, dry, and bitter.

For all the reasons described above, Richard Lyons’ Nursery recommends against planting avocado and citrus species in southern Florida, and it will not again stock them until a cure is found for laurel wilt and citrus greening.

We have Jackfruit

Jackfruit on the tree

Artocarpus heterophyllus (Jackfruit) on the tree.

I know some of you have been waiting since last season ended. The wait is finally over. The jackfruit is back, and we have a beautiful fruit this year.

If you aren’t familiar with jackfruit, this is a tropical treasure. It has a unique flavor somewhere between banana and pineapple mixed with other tropical notes of flavor. The spiny fruits are spectacular in size and can get upwards of 70 pounds.

For a really unique experience, come by our nursery in Miami today and buy some jackfruit for a taste of this Asian treasure.