Jatropha (2018)

By Bob Williams (October 2018)

I am looking at my plants, hoping that one calls out my name for an article. The past articles have been easy. They have been the ones for my caudex experiment. As I look through the plants, one draws my attention. I pull the tag and start looking for information. I find that the selected plant has all kinds of uses. Some species are relatively small, while others are large trees. They are found in both the Eastern and Western Hemispheres. The genus I selected is Jatropha, and the plant in my collection is J. berlandieri.

The genus Jatropha is in the family Euphorbiaceae in the major group of flowering plants known as angiosperms. The Plant List includes 353 scientific plant names for the genus Jatropha. Of these, 190 are accepted species names.

The plants are found in warmer climates worldwide, with most species found in Central American and the Caribbean region. J. unicostata, found on the island of Socotra, is one of the most dominant species on the island. Many of these plants have been introduced from the New World to various regions. One of the most notable is J. curcas. This species is a tree that can grow up to 30 feet tall. Four hundred years ago, traders introduced the plant to India for use as a natural fence to contain livestock.

One of the most amazing things about jatrophas is the wide number of commercial uses the genus has. The seeds of Jatropha plants have very high oil content. In addition, the oil is very “clean,” in that little refining is needed. The oil burns smoke-free and is used in lanterns. Jatropha oil is also used as a lubricant for machinery and to soften leather.

One of the most important qualities of the oil is that it can be used in making biofuel. The seeds of J. curcas contain 40 percent oil by weight – more oil than soybeans contain. J. curcas is currently cultivated for biofuel in 32 countries around the world, including the United States. A major advantage in cultivating J. curcas is that it can survive in dry and somewhat infertile soils where other food crops cannot be grown.

The oil is only one use. The seeds of some plants are used to make dyes, most notable red and blue. After the seeds are pressed for oil, they are pressed into “cakes” and used as an organic manure rich in potassium, phosphorous and nitrogen. The cakes can be found at Walmart stores. The oil is used on domestic livestock for skin diseases, sores and rheumatism.

The roots are believed to act as an antidote for snake bites. Silkworms consume jatropha leaves in their diets. Some jatropha seeds are used to produce insecticides, while others are used as a medicine for constipation. A scale insect that feeds on the leaves causes a “lac” or resin to seal the wounds. This lac is used to make a fine varnish for guitars.

Many Jatropha varieties are commonly used as outdoor landscape plants. These plants cannot tolerate prolonged frost. They are rated for Zones 10 and 11 in the United States and are marginal in Zone 9b.

The University of Florida Department of Agriculture recommends both J. integerrima and J. multifida as low-maintenance, drought-tolerant landscape plants. They flower for most of the growing season and attract a wide variety of butterflies. They are found in most nurseries in southern Florida. They grow well in pots and can be pruned as small shrubs. If you don’t mind moving plants in and out of the house, these could be species to consider in St. Louis.

The plant in my collection is J. berlandieri, which is also known as J. cathartica. It is one of the few caudiciform plants in the genus. Bihrmann’s Caudiciforms lists 15 Jatropha species to which people with our addiction would be attracted.

J. berlandieri is native to Texas, Mexico and Central America. It grows among the brush in clay soils in hot, arid regions. This plant has adapted to prolonged periods of drought and can survive on stored water for many months without rain. Its nickname is buddah’s belly or the baseball plant.

This is a slow-growing plant. The caudex grows to a height of 6 to 8 inches and a diameter of 8 to 12 inches. Once potted, it will take many years before repotting is required.

During the growing season, branches that come from the center of the plant may grow 6 inches. This plant produces small, clustered flowers throughout much of the growing season. The flowers can be pink to deep red. I have seen hummingbirds attracted to mine this summer.

J. berlandieri is a summer grower. Keep it in a dry area in bright light and do not overwater. It can tolerate full sun. During the fall, the branches will dry up and die. Once dry, they can be cut.

This plant is prone to root rot if subjected to cold and wet soil. It should be kept in a room that does not go below 50 degrees F. Do not water until the branches sprout from the caudex around April or May. It should be one of the last plants taken outside in the spring. Like any succulent, it should be potted in a coarse, well-draining soil mix. Water when the mix is completely dry.

Sources:
Llifle Encyclopedia of Succulents – http://www.llifle.com/Encyclopedia/SUCCULENTS/Family/Euphorbiaceae/11601/Jatropha_cathartica
aumkiipure – http://www.aumkiipure.com/uses-of-jatropha.html
University of Florida, IFAS Extension – Jatropha: An Alternative Substitute to Fossil Fuel – http://edis.ifas.ufl.edu/hs1193
University of Florida, IFAS Extension – http://gardeningsolutions.ifas.ufl.edu/plants/trees-and-shrubs/shrubs/jatropha.html
Biodico – http://biodico.com/technology/feedstock-development-testing/jatropha/
Bihrmann’s Caudiciforms – http://www.bihrmann.com/caudiciforms/DIV/ijkl.asp