The mangosteen, Garcinia mangostana, is notoriously difficult to cultivate outside of its native tropical habitat. Growing this tree in California is generally considered extremely difficult, making commercial-scale production impossible. Success is limited only to highly specialized, protected microclimates managed by dedicated hobbyists, as the vast majority of California lacks the consistent, year-round environmental conditions this ultra-tropical tree requires.
The Mangosteen’s Required Climate Conditions
The mangosteen tree has evolved to thrive exclusively in wet, equatorial zones, demanding an environment with nearly unwavering consistency. Ideal growing temperatures are warm and narrow, ranging from approximately 75°F to 95°F (24°C to 35°C), where growth is optimal and continuous. The tree’s growth rate significantly slows when temperatures drop below 68°F (20°C).
This species is highly intolerant of cold; young trees die if exposed to temperatures below 40°F (4°C), and mature trees can be killed below 37°F (3°C). The mangosteen also requires extremely high relative humidity, ideally sustained above 80% for optimal growth and fruit development. It prefers rich, deep, well-drained soil that is slightly acidic, with a pH range of 5.0 to 6.5. Consistent moisture and high annual rainfall are also necessary.
Why California’s Mediterranean Climate Poses Problems
The typical Mediterranean climate found across California presents multiple climatic obstacles that fundamentally conflict with the mangosteen’s tropical needs. The most significant limiting factor is cold sensitivity, as even the mildest California winters can be fatal to the tree. Coastal areas in Southern California may see average winter low temperatures around 47°F, but periodic cold snaps can easily dip below the 40°F threshold that kills young trees. Inland regions, such as the Central Valley, experience even more severe low temperatures, sometimes dropping into the mid-30s or lower, making outdoor cultivation virtually impossible.
A second major hurdle is the state’s severe humidity deficit, which is characteristic of the dry-summer climate. The mangosteen requires relative humidity above 80%, but California’s annual average humidity is much lower, with Los Angeles averaging around 52%. Afternoon humidity levels in inland agricultural centers like Fresno and Bakersfield often drop to 40% or less, which causes severe stress, leaf scorch, and desiccation for the mangosteen.
California’s soil composition adds a third challenge, as most of the state’s agricultural land, particularly in the south, is naturally alkaline, with a pH often exceeding 7.3. This contrasts sharply with the slightly acidic soil (pH 5.0-6.5) the mangosteen requires to properly absorb nutrients. This alkaline environment prevents the tree from properly absorbing necessary nutrients.
Specialized Growing Techniques for Rare Success
Achieving any success with mangosteen in California necessitates bypassing the natural climate limitations through costly, labor-intensive specialized methods. The most common strategy is container growing, which allows the tree to be moved indoors or into a protected structure during the cold winter months. This mobility is essential to prevent exposure to temperatures below 40°F, which would otherwise kill the plant.
Dedicated growers often rely on greenhouse cultivation to create a completely controlled environment year-round. This structure provides the necessary temperature control and, crucially, allows for the installation of misting systems to maintain the extremely high relative humidity the tree demands. Even within a greenhouse, growers must manage the soil carefully, amending the naturally alkaline California soil with sulfur or other materials to achieve the required acidic pH.
A few highly protected microclimates, typically small, sheltered areas very near the Southern California coast, may support an outdoor tree with constant attention. However, these successes are rare, requiring the use of shade cloth to prevent leaf scorch in the dry summer heat and necessitating frost protection during winter cold snaps. Such efforts rarely yield commercial-level harvests due to the high cost and intensive maintenance required.