Cashew Cultivation and Uses

• Cashew Production

Cashew Apple and Nut

• The cashew tree (Anacardium occidentale) produces two main parts: the cashew apple and the cashew nut.
• The cashew apple is considered an accessory fruit.
• The cashew nut is the true fruit of the cashew tree.

Taxonomy of the Cashew Tree

• Kingdom: Plantae
• Division: Magnoliophyta
• Class: Magnoliopsida
• Order: Sapindales
• Family: Anacardiaceae
• Genus: Anacardium
• Species: A. occidentale

Introduction to Cashew

• Cashew (Anacardium occidentale) belongs to the flowering plant family Anacardiaceae.
• Cashew is native to tropical America, specifically Mexico, Peru, Brazil, and the West Indies.
• The Portuguese introduced cashew to India and Brazil around the 15th century for afforestation and soil conservation.
• Cashew has become a major foreign exchange earner, second only to tea and coffee.
• Cashew nut is a top-ranked and important nut grown worldwide.

History of Cashew in Nigeria

• Cashew's presence in Nigeria dates back to the 15th century, initially used for afforestation and erosion control in Eastern Nigeria.
• Commercial cashew plantations began in Nigeria in the early 1950s, established by the Eastern Nigeria Development Corporation (ENDC) at Oghe, Oji, and Mbala.
• The Western Nigeria Development Corporation (WNDC) also established plantations in Iwo, Eruwa, and Upper Ogun.
• Cashew planting spread from these locations to other parts of Nigeria, especially the Central and Northern States.
• Research on cashew production and its uses started at the Cocoa Research Institute of Nigeria (CRIN), Ibadan, in 1971.
• The introduction of the Brazilian cashew biotype, with improved nut and kernel quality characteristics by CRIN, increased the crop's spread and popularity in Nigeria.

Climatic Requirements for Cashew Cultivation

• Cashew is a tropical plant that can thrive even at high temperatures.
• Young cashew plants are sensitive to frost
• Cashew distribution is limited to altitudes up to 700 m above mean sea level, with temperatures not falling below 20°C for prolonged periods.
• Ideal cashew growing areas have temperatures ranging from 20 to 30°C and annual precipitation of 1000 - 2000 mm.
• Temperatures above 36°C during flowering and fruiting can negatively affect fruit setting and retention.
• Heavy and evenly distributed rainfall throughout the year is unfavorable for cashew yield.
• A climate with a well-defined dry season of at least four months is needed for the best cashew yields.
• Excessive rainfall and high humidity coinciding with flowering may cause flower/fruit drop and fungal diseases.
• Cashew is drought-resistant.

Edaphic Requirements for Cashew

• Cashew can grow in poor soils, but performs better in good soils.
• Deep, well-drained sandy loams without a hardpan are the best soils for cashew.
• Cashew also thrives on pure sandy soils, but mineral deficiencies are more likely.
• Water stagnation and flooding are detrimental to cashew.
• Heavy clay soils with poor drainage and soils with a pH above 8.0 are unsuitable for cashew cultivation.
• Excessive alkaline and saline soils do not support cashew growth.
• Red sandy loam, lateritic soils, and coastal sands with slightly acidic pH are the best for cashew

Planting Material for Cashew

• Fresh seeds that sink in water should be planted upright in planting bags with loose, sterilized soil.
• Plant bags for cashew should be 350 to 400 mm deep to accommodate the fast-growing taproot.
• Cashew nuts should weigh between 8 and 9 grams and have a density of not less than 1.0.
• Vegetative propagated planting material is necessary for higher and early yield.
• Techniques like grafting, budding, and layering have been tried in cashew with varied success.
• Softwood grafting has been found suitable among vegetative methods, giving 60% success.
• Self-pollination and cross-pollination are important in cashew seed formation, leading to great variation in seedlings.
• Selected trees should be multiplied by grafting or air layering for vegetative propagation to ensure the best production and quality.
• Trees that bear fruit early and grow vigorously are selected for propagation
• Trees with yellow to grey-brown apples show the most resistance against anthracnose and produce the best yields.
• Side grafting and wedge grafting are two practiced grafting techniques.
• Grafting should start early with 3-4 month old seedlings and planted in the orchard to prevent taproot bending.

Land Preparation for Cashew

• For agricultural lands, the land should be thoroughly ploughed and levelled.
• For forestlands, clear the jungle well in advance and burn the debris
• Land preparation should be completed before the rainy season, ideally during May-June.

Spacing and Planting Systems (Layout) for Cashew

• A spacing of 7.5m x 7.5m or 8m x 8m is recommended for cashew, resulting in tree densities of 175 and 156 trees per hectare, respectively.
• High-density planting at 4m x 4m, with 625 trees per hectare initially, can be thinned to a final spacing of 8m x 8m.
• Planting cashew at a spacing of 10m x 5m on level sites is advantageous, providing a tree density of 200 trees per hectare and space for inter-crops during the initial years

Digging and Filling of Pits for Cashew

• Digging of pits should be done well in advance, approximately 15-20 days before transplanting in May-June.
• Cashew can be planted in pits of 60cm x 60cm x 60cm size in soils with normal strata.
• Pits of 1m x 1m x 1m size are recommended for hard lateritic soils.
• Keep topsoil and subsoil separate and allow them to wither under the sun to help manage termites and ants.
• Burning debris and forest wastes inside the pits is advantageous before planting.
• Fill the pits with topsoil mixed with farmyard manure or compost (5 kg), poultry manure (2 kg), and rock phosphate (200 g).
• Add Benzene hexachloride (BHC) at 100g per pit to the soil mixture to mitigate soilborne diseases.

Fertilizing Cashew

• Manure and fertilizer application is limited for cashew.
• Maintaining an adequate N:P:K ratio in the soil is essential for better yield.
• Apply 10-15 kg of farmyard manure per plant to ensure adequate organic matter in the soil.
• Fertilizers for a mature cashew tree are 500 g N, 125 g P2O5, and 125g K2O per tree per year.

Weeding and Weed Control for Cashew

• Until tree canopies provide shade, regularly weed around tree trunks to a radius of about 2 meters.
• Slash the rest of the orchard undergrowth at least twice a year.
• Apply herbicides or weedicides after slashing, well in advance of the rainy season if the undergrowth is dense.
• Apply 2-4 D at 4 ml/litre of water, followed by Grammoxone at 5 ml/litre of water.
• Approximately 400 litres of spray is required to cover one hectare

Training and Pruning Cashew Trees

• During the initial phase of orchard establishment, regularly remove shoots arising on the rootstock to promote better scion growth.
• Training young trees during the first three years is essential to develop uniform canopies.
• Juvenile phase training involves removing basal branches and water shoots.
• Train plants to a single stem and allow branches to grow about 0.75-1 meter from ground level.
• Remove deformed branches during the first few years
• Proper staking is essential, as cashew trees tend to spread their canopies and lodge easily
• Maintain trees by topping off the main stem at 4-5 meters from ground level.
• Properly trained trees facilitate orchard operations such as terracing, weeding, fertilizer application, nut collection, and stem/root borer infestation control.
• Carry out pruning in August-September at least once every three years to remove unwanted growth and provide adequate sunlight into the canopy.
• Since fruiting is only encouraged from the third year, de-blossom flower clusters during the juvenile phase.

Pests and Disease Control for Cashew

• More than 60 species of insect pests have been identified in cashew
• Major pests include the tea mosquito bug, stem/root borer, leaf miner, leaf and blossom webber, and flower thrips.
• Efficiently manage the tea mosquito bug (Helopeltis antonii) by checking the pest population on the cashew crop and alternate crops.
• No major diseases that cause economic losses have been reported so far in cashew
• Hosts such as neem, drumstick, cocoa, and guava can help control tea mosquito bugs.
• Three sprays at flushing, flowering, and fruiting stages with endosulfan or monocrotophos (0.05%) for the first and second sprays and carbaryl (0.15%) for the third spray can effectively control tea mosquito bugs.

Harvesting Cashew Nuts

• Bearing commences after the third year of planting, with full production by the tenth year.
• The economic life of a cashew tree is about 25 years.
• The main harvesting season is from February to May.
• Farmers often harvest their crop before it drops to prevent pilferage, affecting the quality of the kernels.
• The optimal harvest stage is when nuts drop to the ground.
• High-quality nuts are obtained when freshly fallen nuts are separated from the cashew apples and sun-dried for 2-3 days. Drying brings the moisture percentage to below 9 percent from about 25 percent
• Drying helps to retain the flavor and quality of the kernels.
• When cashew apples are used for processing, harvesting should occur before they drop.
• A maturity test involves floating nuts in water: mature nuts sink, while immature, unfilled nuts float.
• Gather nuts weekly during the harvest season.
• Cashew apples for the fresh fruit market should be harvested daily.

Cashew Yields

• Approximately 92% of trees yield by the third year post-planting.
• Average yield per tree increases from about 2 kg at 3-5 years, to 4 kg at 6-10 years, and to 5-10 kg at 11-15 years of age.
• Trees yield in excess of 10 kg as they get older.

Processing Cashews

• Drying
• Roasting
• Shelling
• Removal of testa
• Grading
• Packaging

Uses of Cashew

• Cashew Nut
  • Cashew nut is versatile and the kernels are rich in nutrients
  • Kernels are used in cocktail parties and confectioneries.
  • Kernels are mostly salted, low in carbohydrates, and rich in proteins, fats, and vitamins.
  • Kernel oil is superior to olive and almond oil.
  • Cashew nuts are a common ingredient in Asian cooking and can be ground into cashew butter
  • They have a high oil content and are used in other nut butters
  • Cashews contain 180 calories per ounce (6 calories per gram), with 70% from fat
• Cashew Apple
  • Can be eaten for its juicy but acidic pulp
  • Can be made into jam, chutney, or beverages.
  • It is juicy and rich in vitamin C but underutilized
  • Tasty drinks can be prepared from cashew apple mixed with lime, pineapple, or grape juice.
  • Jam, chutney, pickles, and wine can also be prepared.
  • Contains much tannin and is very perishable
  • Is discarded after cashew nut removal in many parts of the world
• CNSL (Cashew Nut Shell Liquid)
  • Has industrial uses, including automobile and airplane brake fluid, adhesives, paints, varnishes, insecticides, and electrical insulation.
• Resins and gums from fruit stems or bark
  • Used as a varnish for books, wood, and flooring to protect against insects
• CNSL Fractionation
  • CNSL fractionation is similar to petroleum distillation, yielding solids for brake linings and amber-colored liquid for phenalkamine curing agents and resin modifiers.
• Phenalkamines
  • Used in epoxy coatings for marine and flooring markets because they have intense hydrophobic properties and are chemically active at low temperatures.
• Traditional and Modern Medicines from Cashew Tree
  • Cashew leaves, bark, and juice from the cashew apple have many medicinal properties
  • In Brazil, cashew bark teas treat diarrhea, while caustic shell oil treats skin infections, warts, intestinal worms, and parasitic larvae. - Teas and fruit juices from the cashew apple and leaves are antimicrobial, anti-inflammatory, astringent, diuretic, and hypoglycemic
  • The active ingredients are tannins, anacardic acid, and cardol
  • Shell oil and fruit juice are used in facial peels and scalp conditioners and shampoos.
  • The cashew apple, as it contains up to 5 times more vitamin C than citrus and strawberries, has long been used as a nutritional supplement
• Nutritional Value of the Nuts
  • The nut contains 47% fat, 21% protein, and 22% carbohydrate
  • It also contains vitamins, especially thiamine
  • Cashew nut proteins are complete, with all the essential amino acids.

Cashew Value Chain

• The raw cashew nut industry in Nigeria yields N23 billion annually from the production of 120,000 metric tons of cashew.
• The industry provides livelihood for over 300,000 families and has created over 600,000 jobs.
• 80% of raw cashew nuts from Nigeria are exported to India, Vietnam, and other countries

Defining the Cashew Value Chain

• Value chain refers to the set of value-adding activities a product undergoes from production to delivery to the final consumer.
• The cashew value chain encompasses the entire process of producing, processing, and distributing cashew nuts, from farm to consumer.
• Includes various stages and activities that add value to the cashew nut.
• Shows how value is added and how cashews are modified from the farmer to the final consumer.
• Its aim is to add more economic value to the nut and make it more acceptable in the export market.

Stages in the Cashew Value Chain

• Producers/Farmers: Smallholder farmers who grow the nuts through planting, nurturing, and harvesting cashew apples and nuts.
• Harvesting/Collectors: Carefully remove cashew apples from trees and collect nuts.
• Shelling: Cashew nuts are removed from their hard shells, impacting the end product's quality and appearance.
• Drying: Nuts are spread out to dry to reduce moisture, preventing mold and spoilage, using sun drying or mechanical drying.
• Grading and Sorting: Cashew nuts are graded and sorted by size, color, and quality to ensure only high-quality nuts are processed.
• Roasting: Cashew nuts are often roasted to enhance flavor and remove remaining moisture using dry or oil roasting methods.
• Wholesalers: Purchase and store the nuts.
• Processors: Remove shells from nuts to produce the kernel
• Retailers: Sell the nuts to consumers.
• Exporters: Ship nuts to international buyers
• Consumption: Consumers purchase and consume cashew nuts as snacks, ingredients, or in culinary applications.
• Agrochemical Sellers: Sell chemicals to the industry.
• By-product Producers: Create products from cashew nut by-products like cashew nut shell liquid (CNSL).

Value Addition for Cashew

• Flavoring, seasoning, or packaging cashew nuts in unique ways for specific markets.
• Continuous research and development to improve cashew cultivation techniques, processing methods, and product innovations.

Explore the cultivation, nutritional value, and diverse uses of cashews. Learn about cashew's early introduction to India and Brazil, its economic role in Nigeria, and its ideal growing conditions. Discover the industrial uses of CNSL and the nutritional benefits of cashew kernels.