Coconut palms are tropical plants that thrive best in USDA Plant Hardiness Zone 10 or 11. While portions of Arizona are within zone 10, these areas do not receive enough annual rainfall and the temperature fluctuations are too extreme for long-term coconut palm growth. Avoid planting coconut palms in Arizona.
Soil and Sunlight Requirements
Coconut palms will tolerate a wide variety of soil types and pH, if the soil where they are planted is well drained. While this type of palm is associated with beaches, it is adaptable to inland soil conditions. Coconut palms require full sun.
Coconut palms are not cold tolerant. Ideally, they prefer a year-round temperature no colder than 70 degrees Fahrenheit. Temperatures under 32 F will injure the palms, particularly if the weather change is sudden. Unfortunately, weather in Arizona is prone to sudden weather changes. Night and day temperatures can vary as much as 50 degrees.
The dry state of Arizona receives less than 15 inches of rain annually. Rainfall occurs nearly exclusively during winter and summer rainy seasons. Coconut palms require at least 40 inches of evenly distributed rainfall year-round for successful growth. The amount and distribution of rainfall in Arizona is clearly at odds with the watering needs of the coconut palm.