Palm trees aren’t native to Arizona, but they grow in Phoenix, and in a neighborhood called Mountgrove, regal palms soar like nowhere else in the city. Thick-trunked, lavish silvery-green fronds floating in the desert breeze, they lean skyward above sleepy roads, green yards, and rooftops in vaguely military formation. In all, some 300 palms stand. They are date palms, and not just any date palm. This small suburban stretch is the nearly exclusive home of the Black Sphinx, a world-class date found only in Phoenix and grown largely by residents,…
