Ionia is a frame house near Trevilians, Virginia, that was the centerpiece of a large plantation in the late 18th and early 19th centuries.

It was built as Clover Plains by Major James Watson, the son of a Scottish immigrant, in a fertile area of Louisa County, Virginia that is now a National Historic Landmark District, the Green Springs National Historic Landmark District.

[3] The plantation was the third largest in Louisa County in the late 18th century, leading to the nickname "Wheat Stacks" for Watson as a result of his prosperity.

The Watson family went on to build a number of houses in the Green Springs area.

One-story wings flank the main block on either side, with an ell to the rear.