The edible portion of the cashew, often called a nut, is botanically a seed that grows on the end of a kidney-shaped drupe, which hangs from the fleshy cashew apple. Commercial cultivation of the Anacardium occidentale tree is virtually non-existent throughout the contiguous United States. Cashews consumed domestically are primarily sourced from international markets, which possess the ideal climate and necessary infrastructure for large-scale production. The distinct growing requirements and specialized processing needed to make the seed safe present barriers to commercial farming in most of the U.S.
The Cashew Tree’s Specific Climate Requirements
The cashew tree is a tropical evergreen that requires high temperatures to flourish and produce nuts reliably. Optimal growth occurs between 68 and 86 degrees Fahrenheit (20 to 30 degrees Celsius). The plant cannot tolerate frost or prolonged cold periods; even brief exposure to freezing temperatures is detrimental. This immediately excludes the vast majority of the U.S. mainland from viable cultivation.
The tree thrives best in regions with a distinct wet season and a long, well-defined dry season lasting five to seven months. This dry period coincides with the flowering and fruiting stage, ensuring proper pollination and fruit setting. The cashew tree prefers well-drained, sandy loam soils and cannot survive in heavy clay or waterlogged conditions. These specific environmental needs confine the tree’s natural growing range to equatorial and tropical zones.
Limited US Cultivation and Experimental Zones
While commercial cashew farming is absent in the contiguous U.S., limited cultivation exists in specific tropical and subtropical microclimates. The US territory of Puerto Rico and the state of Hawaii offer the most conducive environments, with year-round warmth and tropical conditions. In Hawaii, a few farmers have established small-scale cashew orchards, attempting to develop the crop as a local product, though it remains a niche endeavor.
On the mainland, growing is confined to the southern tip of Florida, such as the Florida Keys, where the climate is frost-free and tropical. Cashew trees here are primarily found in botanical collections or private home landscapes, often grown as novelty trees rather than for nut production. The occasional cold snap that reaches even this far south poses a continuous risk, reinforcing the difficulty of establishing a reliable commercial industry.
The Necessity of Specialized Processing
A significant barrier to domestic cashew production is the toxicity of the raw nut’s shell. The shell contains Cashew Nut Shell Liquid (CNSL), a caustic, viscous oil housed between the inner and outer layers of the shell. This oil is rich in phenolic compounds, notably anacardic acid, which is chemically related to urushiol, the irritant found in poison ivy.
Direct contact with raw cashew shells or CNSL can cause severe skin irritation and blistering. To neutralize this toxic compound and safely extract the edible kernel, raw nuts must undergo specialized high-heat processing. Commercial operations use roasting or steaming techniques, heating the nuts to 180 to 200 degrees Celsius. This process decarboxylates the anacardic acid into less-toxic cardanol, neutralizing the irritant.
This specialized handling requires dedicated infrastructure, ventilation systems, and trained personnel to manage the CNSL’s toxic nature. The cost and regulatory complexity of establishing such facilities in the U.S., combined with the limited domestic supply of raw nuts, make commercial processing economically unfeasible. The CNSL is a valuable industrial byproduct used in resins, coatings, and friction materials, but its hazardous nature requires careful management throughout the processing chain.
Global Sourcing of Cashew Supply
Since the U.S. has no commercial cashew production, the domestic supply relies entirely on imports from countries with ideal growing conditions and established processing capacity. The global cashew market is dominated by tropical nations in Africa and Asia, which possess the necessary labor and infrastructure for the energy-intensive processing steps. The United States is a net importer, with nearly all cashews consumed domestically arriving from overseas.
The top global producers and processors include Côte d’Ivoire, India, and Vietnam. While raw cashew nuts are largely produced in West Africa, processing and shelling are mainly concentrated in India and Vietnam, which have become global hubs for finished kernels. The U.S. market is heavily dependent on Vietnam, the primary supplier of shelled cashews. This global supply chain ensures a steady, year-round availability of processed cashews in the American market.