Japanese Chaff Flower – Control
Q: What is this ornery weed trying to take over my garden. When it started last year, I first thought it was my ‘Black and Blue’ sage but soon discovered it was not. It has a square stem and smooth leaf edges. No discernible fragrance on a hot afternoon.
A: It’s Japanese chaff flower, Achyranthes japonica. It is a perennial plant so thorough and persistent control is necessary. As you have found, it is very invasive. Pull seedlings by hand and spray older plants with glyphosate (click for sources).
Map of the spread of the plant in Georgia