Jacques Descloitres/NASA/Wikimedia
Answer: Hawaii
The first state in the United States that engaged in commercial coffee production is, you guessed it, Hawaii. Coffee was first introduced, rather unsuccessfully, to the island chain in 1813. Over the ensuing decades, different varieties of coffee were planted with little success around the island chain (many of them dying out entirely or only yielding small amounts of coffee beans).
In 1828, the Reverend Samuel Ruggles transplanted some cuttings of coffee plants to the Kona region and, in the process, stumbled upon the most coffee-hospitable region of the island chain. Over time, farming practices and techniques improved and coffee is now grown in multiple regions of Hawaii. The total production per year is between eight and nine million pounds; small change compared to global trade levels, but a high yield for the small amount of land in Hawaii devoted to coffee.