They grow in ordinary garden soil and full sun. Cut back the plants after the first bloom to get a second flush of flowering. Achillea may become a weed if not controlled. Propagation is by division in spring or autumn, or seed. The seed germinates in 2 weeks at temperatures between 65 and 75 degrees.
Light is necessary for seed germination.
Germination time indoors may be as little as 5 to 7 days. Achillea filipendulina Grows 2 to 4 feet tall and the yellow flowers hold their color if cut and dried before they fade. Achillea millefolium Grows 1 to 2 feet tall with white or red flowers, depending on the variety grown. The plant may need some support when in bloom. Visuals associated with this text.