What Is Chaya?
Chaya, commonly known as “tree spinach”, is a perennial shrub and an excellent source of vitamins, fiber, proteins and enzymes. As a year-round source of high-quality food in a wide range of conditions, it could be one of the most important edible-leaved plants in the tropics. Chaya requires little maintenance and is widely cultivated in Mexico and Central America. In Costa Rica, it’s also known as “chicasquil”. Unfortunately, most locals only know it as an ornamental or living fence-line.
Tree spinach grows around 3 meters tall, with a thick main stem up to 4 inches (10 cm) in diameter. It can be cut and kept at a height of around 1-2 meters for easy harvesting. Chaya was long used by the Mayans of the Yucatan Peninsula as a food crop and a medicinal plant. The name “chaya” is derived from the Mayan name “chay”.
There are 2 common varieties of chaya with different looking leaves, however both have similar stalks, growth and nutritional characteristics. Green Dean at Eattheweeds.com was the only source I could find that explained the difference between these two different chaya plants. There seems to be some confusion on names, even among botanists, but below are to two main types you’ll see.
The five pointed “estrella” variety is what we have here in the tropical dry forests of NW Guanacaste, Costa Rica. Some breeds of chaya have spines and are more difficult to harvest, however all are edible. Fortunately, ours are spineless, tasty and simple to collect!
Why Grow Chaya?
The levels of Chaya leaf nutrients are two to threefold greater than most edible leafy green vegetables. It’s perennial, drought tolerant and can grow without any care at all. Chaya also highly disease and pest resistant. Here in Costa Rica, it pops up on the roadsides when rainy season starts. I often take cuttings back to the house while out running and hiking. It’s amazing how many locals have no idea what it is. Free uber-nutritious food growing all over…….and no one takes it!
According to this paper published by Purdue University Chaya is significantly more nutritious than spinach, amaranth and Chinese cabbage:
Chaya leaves were found to contain substantially greater amounts of nutrients than the spinach leaves. The chaya leaf is especially high in protein (5.7%), crude fiber (1.9%), calcium (199.4 mg/100 g), potassium (217.2 mg/100 g), iron (11.4 mg/100 g), vitamin C (164.7 mg/100 g), and carotene (0.085 mg/100 g). The levels of chaya leaf nutrients, in this study, agree with published reports (Martin and Ruberte 1978; Munsell et al. 1949; Booth et al. 1992) and are two to threefold greater than most edible leafy green vegetables. In terms of the average nutritive value, chaya leaves [14.9] is by far superior to other leafy green vegetables such as spinach [6.4], amaranth [11.3], Chinese cabbage [7.0], and lettuce [5.4] (Grubben 1978). While some edible leafy green vegetables are usually good sources of mineral macronutrients (Levander 1990), chaya leaf furnishes appreciable quantities of several of the essential mineral macronutrients necessary for human health maintenance.
Here are Comparisons of nutritional compositions of leaves of “chaya” (Cnidoscolus chayamansa) and spinach (Spinacia oleraceae) per 100 g.
|Crude fiber (%)||1.9||0.9|
|Total CHO (%)||4.2||3.8|
|Ascorbic acid (mg/100g)||164.7||48.1|
|Average nutritive valuey||14.94||6.38|
Vitamin C also ends up in the water when chaya is cooked. If one drinks the broth as well as eating the leaves, only 25 grams of chaya leaves can meet an adult’s daily requirement for vitamin C. What an outstanding health supplement!
While the nutritional value of chaya has been demonstrated, there are many therapeutic and medicinal claims about chaya leaves that have yet to be substantiated. One Purdue study verified anti-diabetic claims about chaya tea. It was administered to diabetic and non-diabetic rabbits and their blood glucose levels were measured over a period of 6 hours.
Here are the results of the experiment:
|Blood glucose level (mg/dL)z|
In diabetic rabbits, after 6 hours, the ones supplemented with Chaya tea had blood glucose levels of 87mg/dL, while the ones with water were at 162mg/dL. That’s a 46% drop in blood glucose levels! Hopefully more research can be dedicated to the medicinal qualities of this plant.
If nutritional reasons aren’t enough, the chaya leaves may be dried, ground and used as supplemental poultry feed. In this 2002 study researchers found that chaya leaf meal could be mixed into corn feed 250 g/kg as a supplement to poultry on a lower protein diet. This may be something to keep in mind if we ever lose access to cheap corn and soy. A food crisis could be right around the corner.
How To Grow Chaya:
Chaya is easily propagated by stem cuttings. Make a 6-12 inches cutting from a woody part of the stem and be sure that there are at least a few nodes on the cutting. Remove all leaves and let the cutting air dry for a 2-3 days. This will allow the cut ends to seal, making them less susceptible to rotting. If you’ve ever propagated moringa, the process is much the same.
When you’re ready, put the cuttings in the ground with 1-2 nodes under the soil and keep moist. Don’t over water, or the cutting will rot. You can also start them in pots or starter buckets first and the transplant them if you’re concerned about them rotting. Chaya is cold sensitive and should be started at the beginning of a warm season. It does fine as an understory shaded plant, so northerners may be able to grow them indoors and bring them outside in the spring. If you have an aquaponics system, don’t both trying to propagate chaya in it, the cuttings will just rot. I’ve tried repeatedly in gravel media without luck, but they might work well in a wicking bed setup.
Inside the stalks there is a white latex sap that can irritate the skin, so gloves are recommended if you’re going to do a lot of chaya choppin’.
After 3-6 months you’ll have a strong chaya plant ready to harvest from. Transplants can also be planted in an established legume living ground-cover. Perennial peanut (Arachis pintoi),which is common in Florida and Costa Rica, is an ideal living ground cover. This is particularly favorable planted on slopes to prevent erosion and control weeds.
Preparing Chaya Safely:
Chaya leaves and shoots are harvested and used much like regular store-bought spinach, however many chaya leaves and shoots contain toxic hydrocyanic glycosides. Cooking chaya in boiling water for five minutes or frying rids the stems and leafs of the poisonous cyanide components. I’m not aware of any reports of acute or chronic cyanide poisoning from chaya, but just to be safe, cook it first. The broths are also safe to drink, as the cyanide compounds boil off quickly.
Chaya — Cnidoscolus chayamansa McVaugh – University of Florida
ECHO Technical Note – Chaya (a great PDF that relays experiences with chaya from around the world)