Northern Spy produces fairly late in the season (late October and beyond). Skin color is a green ground, flushed with red stripes where not shaded. The white flesh is juicy, crisp and mildly sweet with a rich, aromatic subacid flavor, noted for high vitamin C content. Its characteristic flavor is tarter than most popular varieties, and its flesh is harder or crunchier than most, with a thin skin.

Northern Spy is commonly used for desserts and pies, as well as juice and cider. It is an excellent apple for storage, tending to last long due to late maturation.

The Northern Spy was discovered around 1800 in East Bloomfield, New York, south of Rochester, New York, as surviving sprouts of a seedling cultivated from stock brought in from Connecticut that had failed. The Wagener apple is believed to be one of its forebears. It fell somewhat out of favor due to its dull coloration, irregular shape, tendency of the thin skin to allow bruising, and lack of disease resistance, specifically to bitter pit and blossom fireblight, but resistant to woolly aphid and somewhat to scab. It is not widely available at retail outside its growing regions but still serves as an important processing apple in those areas. The Northern Spy is known for taking as much as a decade to bear fruit, unless grafted to a non-standard rootstock. In spite of this, it makes an excellent root stock for grafting other varieties to become standard-size trees.

A Northern Spy apple tree figures in the poem "Conrad Siever" in Edgar Lee Masters' Spoon River Anthology, and in the poetry of Chase Twichell, whose first book Northern Spy was published by the University of Pittsburgh Press in 1981.

A box of Northern Spies was sent to Senator Joseph McCarthy by the news staff of the Toronto Globe and Mail in 1953 as a joke.^[5]

• Apple Use
• USDA Pomological Watercolor Collection