Purple Magic Fingerling Potatoes are not native to Florida but are a Florida friendly food source. The potatoes grow best if planted before March but can still yield produce year-round. For the best yield plant in full sun, with moist but well-drained soil. They thrive in sandy soil. Fingerling potatoes, like all potatoes, can be propagated from potato cuttings. Potatoes are ready to harvest when foliage turns yellow.