Thursday, 26 February 2015 14:36

How do Cashews grow?

Did you know cashews grow on the underside of a cashew apple on an evergreen tree?

  • Latin Name:

    Anacardium occidentale

  • Growth:

    USDA Hardiness Zones 10 - 12  Click here to view USDA Plant Hardiness Zone Map.

    The cashew is a tropical or subtropical evergreen shrub or small tree that is native to Central and South America. The tree produces an apple or pear-shaped “accessory fruit,” known as the cashew apple, but its real fruit is the kidney shaped drupe (or stone fruit) growing at the stem of the cashew apple. The drupe is harvested, roasted, and eaten. Although it is not botanically a nut, it is commonly known as a cashew nut.

    Cashew trees grow up to 50 feet tall, but the shrub-like dwarf version (20 feet tall at full maturity) is more popular because it produces a higher yield of cashew “nuts” and matures earlier than the full size tree. Cashew trees produce reddish pink flowers.

    The trees are very frost sensitive, relatively drought-resistant and fare well in sandy soils in both dry and wet tropical settings. Cashew trees that are grown from seed take up to three years to produce a harvest, but grafted trees produce in as little as 18 months.

     

     

     

  • Propagation:

    Cashew trees can be grown from seed or propagated by air layering or softwood grafts.

    Air layering means that a strip of bark ¼ to ½ inches thick is removed from around a 9 to 12 month old pencil-thick terminal shoot.  The cut portion is covered with damp moss, wood shavings, or ordinary potting soil and wrapped tightly in polythene film.  Roots emerge from the ringed portion in 40 to 60 days when the shoot can be cut off from the parent plant and planted on its own.

    Softwood grafting means choosing healthy seedlings that are 50 to 60 days old to serve as rootstock. Soft wood shoots with dark green leaves of similar thickness (3 to 5 months old, non-flowering) from a high-yielding variety of cashew mother tree are grafted onto the rootstock. Successful grafts show signs of growth in 3 to 4 weeks and are ready to plant at 6 weeks.

     

  • Harvest:

    Cashew trees flower in winter and produce fruit for an early spring harvest. The fruits start off yellow and darken to a deeper red - at which point they are ready for harvest.

    Cashew apples can be eaten or juiced immediately but are not available to purchase commercially, so harvest time is the only time they’re available. Most people who grow cashew trees do so for the “nuts.”

    Fruits are harvested before they fall to the ground and break the cashew pod off the end of the fruit. The cashew pod can be stored for two years as-is or shelled immediately - but beware: beneath the shell lies an acidic resin that burns your skin. The oils found in a cashew shell are similar to those of poison ivy.

  • Storage:

    Shelling

    The easiest method is to freeze cashews before shelling, and to remove the nut kernel from the now solid, frozen resin. 


    A common method of shelling cashews is to roast the nuts over an open fire until the shells crack and resin drips out. The smoke created can be a toxic irritant, so roasting is usually done outdoors. 

    Storage

    Cashews turn rancid quickly due to their high oil content. They can be stored in a cool, dry place in an airtight container, but perish in two weeks or less. Cashews can be stored in the refrigerator for up to 6 months and in the freezer for up to one year.

     

  • History:

    The cashew, or acajú, as the indigenous Brazilian tribe called the Tupi named it, originates in northeastern Brazil. Colonists from Portugal introduced the cashew to the western world after discovering it there in 1578. The cashew’s botanical name, Anacardium occidentale, is a description of their heart-like shape.

    Via Portuguese colonization, the cashew spread to Mozambique, Africa, and later to India at the end of the 16th century. Because the cashew tree is one of the few plants that flourishes in the poor soil conditions of sandy beaches, the Portuguese originally cultivated to prevent beach erosion in coastal areas of colonization, rather than for the tree’s fruit and nuts.

  • Top Producers:

    Vietnam, Nigeria, India, Côte d'Ivoire (The Ivory Coast), and Brazil are the top five cashew producing countries (FAOSTAT, 2011).

     

  • Varieties:

    Cashews are not grown commercially in the United States so few varieties are available or named. Some found outside the United States include: Anakkayam, Kanaka, Dhana, Priyanka, Madakkathara, and Raghav.

     

  • Products:

    Cashews are most commonly eaten roasted or raw in salads, desserts and savory dishes.

    The cashew apple. which is not readily available commercially in the United States, is also edible and used in fruit juices. In Goa, India, it is mashed and the juice extracted for fermentation to be distilled into an alcoholic drink called feni. In parts of Tanzania and Mozambique in Africa, it is also used to make strong liquors.

    Cashews have a variety of non-culinary uses. Cashew shell oil is used in the development of pesticides and fungicides, antibacterials, drugs, and antioxidants. In tropical folklore, it is hailed for its uses as an anti-termite lumber treatment.

    Chemicals identified in cashew oil have proven effective in defending against Streptococcus mutans, a bacteria responsible for dental cavities.

     

  • Top Health Benefits:

    Cashews may be a tough “nut” (remember, they’re not a true nut, but a seed) to crack due to the caustic resin that lies between the shell and the “nut” kernel. Once they are shelled, however, they boast a wealth of health benefits.

    Cashews are low in fats, composed of 82% unsaturated fatty acids. Of these unsaturated fatty acids, 66% are good monounsaturated fats, similar to the heart-healthy monounsaturated fats found in olive oil. When added to a low-fat diet, monounsaturated fats can help reduce the triglyceride levels in the body, which are associated with the risk of heart disease.

    Cashews are high in antioxidants, such as the mineral copper. One serving of cashews contains 98% the recommended daily value of copper, which is related to the elimination of free radicals in the body, lowering cholesterol levels, and the efficient processing of iron.

    Copper helps stimulate the enzymes responsible for cross-linking collagen and elastin in the body, that help with flexibility in the joints, bones and blood vessels.

    Cashews also contain almost ⅓ the daily value of magnesium, which helps to maintain healthy blood pressure by dilating blood vessels. Magnesium helps to prevent muscle cramps and spasms, soreness, muscle fatigue, migraine headaches, menopausal sleep disturbances.

    Magnesium is also vital for bone health. In fact, about ⅔ of the magnesium found in the human body is found in skeletal bones. Magnesium also helps to provide muscle and nerve tone by counterbalancing calcium (which can over-activate nerve cells when in imbalance).

    The cardio-protective benefits, LDL (bad) cholesterol-reducing and HDL (good) cholesterol-increasing benefits of cashews are related to lowered risk of weight gain and obesity.

     

  • Grow it yourself:

    The section on propagation explains how to propagate cashews by air layering or softwood grafts. A cashew grown from seed takes three to five years to produce fruit.

    To plant a cashew tree from seed, the entire seed is necessary - not just the nut kernel. It is best to purchase cashew seeds from a nursery to better ensure fruitful results.

    Cashews are a tropical tree that grow best in USDA Hardiness Zones 10 through 12. The cashew tree is highly frost sensitive. Daytime temperatures should not drop below 50 degrees Fahrenheit, and should average 80 degrees Fahrenheit for the year.

    Seeds can be planted directly in soil, in early spring. Plant seeds at a depth of three inches, and if planting multiple seeds, space at least 30 feet apart so that growing trees have room to spread.

    Plant in a sunny location with sandy, well draining soil. The trees are happy in sandy soil conditions that are generally considered “poor,” and do not require much fertilizer. Apply fertilizer composed of nitrogen, phosphorus and zinc once or twice per year.Because cashew seeds germinate well, it is only necessary to plant one seed in each location. Water establishing plants, but do not water to excess.

    Once the seed is established, cashew trees require little care because they are drought-resistant and not picky about their soil requirements.

     

     

  • Recipe: