An Ethnobotanist’s Reflections on One of the World’s Most Important Food Crop Families, Cucurbitaceae: Including Squash, Melons & Cucumbers

My passion for Cucurbits started somewhere before my 5th year, by the time I was seven I was so excited about them that I asked my parents to give me squash for my birthday. Now some 43 years later I am still “crazy” about squash and all their kin. As a World Food Plant Ecologist—one who is a true generalist, it is indeed difficult to claim that I have a favorite plant family, however, if I was held at gunpoint and forced to answer I would have to concede that my favorite group is indeed the Cucurbits. In the years since my first introductions to squash in the gardens of my grandparents and elderly neighbors, I have been blessed to travel around the world dozens of times studying the very same things that fascinated me as a child.

Fortunately for me and for the sake of biodiversity, the world is a very big place with lots of things to discover. For a plant eater and plant hunter it is amazing that after all these years of studying that there are still “new” Cucurbits to “discover".

“Look around you and discover nature’s works are at hand and we have been remiss to notice”

–Joseph Simcox

In January of 2014 I went on a trip to Central America, my brother Patrick and I agreed to meet up and take 10 days botanizing. Patrick met me at the airport in Panama City and we immediately embarked on the “expedition”. We were intent on collecting and locating as many cucurbits as possible. We drove around Panama and stopped at every sight of fruit or produce and we made collections of dozens of landraces of squash and were introduced to a couple of fruits that are all but unknown, these were extremely impressive cucurbits. One of them, Cionosicyos macranthus, is so obscure that the natives themselves have endowed it with a rather ridiculous “foreign” common name. They call it the “Chinese Passionfruit” as if it originated in China when in fact it is an endemic of the region! First learning about the existence of this fruit in a book, my brother and I worked on sleuthing out its whereabouts.

After asking dozens of people about the “Maracuja Chino”, we finally found someone who knew what we were talking about. When they took us to a bearing plant we were amazed to find how productive the vine was—as many as a couple of hundred fruits hung from one plant that had climbed over a tall tree in it’s search for the sun. The fruits of Cionosicyos are gorgeous. They have a shiny yellow porcelain exterior that when cut reveals a deep orange-pink flesh that includes a center with seeds floating in the “liquid like pulp”.

Both the flesh and the “liquid pulp” are delicious. The natives of central America who know of the fruit value it highly, they make a drink out of it that is variously referred to as a “liquado” a generic name for fruit drinks that are made in blending machines, sometimes with the addition of milk and sugar to enhance the flavor. The flavor of the Cionosicyos fruit is very akin to that of a very tasty papaya. My brother Patrick Simcox, who is also a botanical explorer, said that it was one of the most delicious fruits that he had ever tasted. Having impressed us so, the question we posed is: “Why is this fruit not being globally cultivated in the tropics?”

The second amazing cucurbit species that we “discovered” in Central America grows as an endemic in Costa Rica it is known as “Tacaco”. Tacaco or Sechium tacaco is almost unknown outside of Costa Rica, within the country it is well known, however as diets “modernize” to include more and more processed foods the traditional appreciation for this vegetable seems to be dwindling.

My brother and I found untended Tacaco vines growing in profusion on a country road not far from the northern border of Panama. The country folk were amused that two “Gringos” were so interested in something that they themselves had come to overlook. The vines that we had discovered were loaded with small 4–6 centimeter (2˝-2˝1/2) long fruits. While young and tender (before the skin hardens and they become fibrous) these Tacacos are one of the most exquisite of vegetables. We harvested several bags of them for our own trials and we were amazed by the edibility of the tender boiled fruits. The taste can vaguely be likened to a summer squash with the qualification that it also tasted “nutty” or even avocado-like. A few scientific papers suggest that it is much more nutritious than it’s close relative the Chayote, Sechium edule.

To our knowledge neither of these extraordinary fruits are being cultivated commercially even in the countries where they are known. It is further proof that promising food plants can easily be lost. If traditions and cultures change. The dilemma is not limited to any particular region but seems to pandemic in occurrence.

A world away in East Africa I was astounded to find that very few people were still cultivating he Eastern African Pumpkin, Telfairia pedata. In October 2010 I had traveled to East Africa specifically to track down amazing yet underutilized fruits and vegetables, among them was Telfairia pedata.

I had known of the existence of this amazing plant for many years and was indeed anxious to track it down, the day came when I arrived in Fort Portal. My friend Chris Kaija, of Tooro Botanical Gardens, showed me my first fruit, it was an enormous hanging green orb! This “vegetable” is being ignored, despite the fact that it produces an exquisite giant seed that at one time was exported to England under the name of “Queen’s Nut”. One can only imagine why it is no longer being shipped since at one time it was a real special commodity. Perhaps the trade was interrupted during the horrendous Idi Amin years and never recuperated or was forgotten. In any case the seeds of Telfairia pedataare definitely worthy of being called the Queen’s Nut, they are delicious. I acquired several pounds of seeds and had to stop myself from eating my propagation material precisely because they were so tasty! This plant urgently needs more attention. In Western Africa its close relative is Telfairia occidentalis; The African Fluted Pumpkin. Unlike with T. pedata, the seeds of T. occidentalis need to be cooked before consumption. One of my good friends, Roy Dansforth has been kind enough to send me photos of this enormous fruit. Fluted Pumpkin fruits can get up to a meter long and may have hundreds of seeds. In the west it has also been called Oyster Nut. Presently I am in communication with a Nigerian Professor, Bosa Okoli who is writing a book on the Telfairia. According to him cultivation is actually increasing in Nigeria as it is being promoted as a traditional vegetable.

Southern Africa is rich in wild cucurbit diversity and a great number of the species are not only edible but exquisite food sources. In Western Botswana, my team and I had the incredible opportunity to go on a “desert hunt” with the Kalahari Bushmen. There my objectives were happily fulfilled as we stalked out fruits and plants of many edible cucurbits. Among them, The Gemsbok Cucumber, Acanthosicyos naudinianus. The fruit of which is somewhat barrel shaped with blunt protuberances poking out of the skin. It looks artificial, like some pastel yellow pet toy. Sources have shared with me that certain forms of the Gemsbok Cucumber exist that are so “sweet” that they can be eaten raw, most, however, still need to be cooked before eating. I had a good laugh when I experimented on my brother telling him to taste a ripe fruit, “How does it taste?” I repeated. “It tastes terrible” he replied, so most are probably cooked. The Kalahari Bushman do this creatively by burying the ripe fruits in the ashes of last evenings fire. After a few hours the fruits are cracked open and the liquid interior seeds and all is sucked out much as one could envision someone eating a raw egg after carefully tapping open the top.

Several hundred miles away on the Namibian Coast we came face to face with one of the most enchanting plants on the planet. Growing in swelling dunes not far from the sea is the Nara Melon, Acanthosicyos horridus. The Nara is a fruit that I dreamt of, what mystery. A Cucurbit without leaves, that grows in barren sands that produces a relatively large (up to a kilo) fruit that has been revered by the Topnaar people for ages. Both its fruit and seeds are a valuable food resource. While we were there we watched as the Topnaar boiled the ripe melons down to a syrupy concoction and then poured the fruit pulp on to the hot sand. The pulp dries making a type of “fruit leather” which is stored and used later. There is also a commercial aspect to the Nara harvest, known as “Butter Pips” the seeds are collected and sold to South Africa where they are a traditional snack food. Despite these uses the Nara melon is still some obscure oddity. It indeed has potential to be grown as a crop in the right circumstances but little if any attention is being given to it!

With so many species to mention in Southern Africa it is difficult to limit the scope, however, another cucurbit stands unique in the sandy bushlands of the Kalahari. Cucumis kalahariensis is not sought out for its fruit but rather its large tapered juicy white—carrot like—roots! This is such an extraordinary find in the desert that the bushman have come to rely on it as a food and water source in their sojourns. I was able to taste my first “Kalahari carrot” in February 2012. I dug the root out with some bushmen standing overhead… pulling out the root, they motioned for me to clean off the skin, I scraped it off eagerly with my teeth and bit in…delicious! The roots are tender, succulent and crunchy not too unlike Water Apple, Syzygium samarangense, fruits. I could easily become an addict of them if lived in the desert!

To this author’s knowledge, little if any effort has been made even to cultivate wild germ-plasm in trials. Nothing has been done to select varieties, yet its potential for food production in hot desert areas is exceptional. The thin exterior skin of the root although bitter, is easily removed by abrasion making this plant a most promising future food resource.

A world away in my home country, the USA, cucurbits were also used as food resources. Much of the knowledge of that use is long lost. However enough vestiges remain that we can be provoked with the possibilities. Among the possible food crop cucurbits is the so called Buffalo Gourd, Cucurbita foetidissima. Both the immature fruit and the seeds have potential. The plant itself produces what has been claimed to be one of the most bitter substances known, nevertheless, the seeds were processed for meal by the Native Americans and are known to be very nutritious. The plant is a gregarious perennial that takes heat, drought and abuse. I love to see their vines sprawling in all directions loaded with yellow fruits as a drive down the back roads in places like West Texas. I have commented to horticulturists that it would make a wonderful seasonal groundcover for drought susceptible areas, the leaves are glaucus grey and triangular and very pretty. The Buffalo Gourd is treated like an weed by dryland farmers, but what they don’t know is that this weed may one day be someone’s crop. It certainly needs to be worked with by scientist and the inspired because it has huge potential as a crop for hot dry areas.

In Southern America, there are also wonderfully adapted species of edible cucurbits. The genera Melothria, Cyclanthera and Sicana all being among my favorites. Melothria dulcis is a delightful fruit that is filled with a juicy flesh mass not unlike the interior of a passionfruit, in ways it resembles one. I found my first wild Melothria dulcis vines along the Pacific Coastal highway in Guatemala. The vines were loaded with ripe fruit and I collected a ton of them and ate them and saved the seeds. The seeds are very unusual because they are resplendently covered with fine “shimmering” golden hairs, making them almost look metallic! Melothria scabra has been widely introduced in the United States as a “mini-cucumber” one trade name in which it has marketed in both the US and Europe is “Pepino”. They grow wild on fences all through Mexico and Central America, children relish the green ones, but as word goes, don’t eat the dark black ripe ones, they have powerful laxative properties. The fruits are small, 2-3 centimeters long, but make crunchy, juicy and eye appealing additions to salads so they are popular with chefs who purchase them to make their entrées more exciting. This fruit has great potential around the world as an annual warm weather crop.

Cyclanthera pedata, is a plant which has been domesticated by presumably the Incas or their ancestors. It grows in cooler moister conditions and produces bumper crops of large slipper like fruits. The inner cavity is hollow so the mode of use is to scoop the seeds out and fill it with fillings and bake it. I have seen the plant growing and fruiting as north as Oslo, Norway and am presently growing the plant in New England where it is thriving and setting buds. It shows no photo period sensitivity, and seems highly adaptable and hardy. It seems to be a very good vegetable resource for moist cooler climates. Several other edible Cyclanthera species exist all which are fascinating.

The Casabanana, Sicana odorifera, is a delightful domesticated cucurbit grown throughout central and southern America. Sicana is a monospecific genus. I saw my first fruits years ago while on a trip to Guatemala. Since then I have promoted its cultivation and in recent years it has been grown in the US as a long season annual. It certainly has great potential for further selection, improvement and adaption. Genetic diversity abounds, yellow, chocolate, black, red and orange fruits are known. The fruit is traditionally either baked (much like a squash) or made into fruit smoothies. So fragrant are the mature fruits that they have been used to perfume homes. The young fruits can be cooked an eaten as well. The author hopes that this fruit will find itself being grown all around the planet as have other American cucurbits!

These are just a few of my “global” cucurbit “discoveries”. Every since I was a small child I have been mesmerized by their seemingly endless forms. To write about them here is both nostalgic and inspiring. Nostalgic to recall all of these great adventures, and inspiring because in some small way I hope I have shared something fresh and fun with you the reader. I continue to contend that the scientist citizens greatest tool is passion and curiosity. I hope that I never lose my childlike curiosity, and I hope that you the reader, never does either. Let us share the wonders of nature with all. In the years ahead it is my own hope that many of these most worthy fruits find the attention that they deserve, because they are nature’s gifts to man.