A couple of years ago I found a cluster of yarrow growing in the backyard. I noticed the foliage when the plants were small, maybe half a foot tall. Rubbing a leaf released the “flower arrangement” scent that confirmed I was looking at Yarrow, Achillea millefolium.
Learning the scents that plants make is only secondary to learning their physical characteristics to identify them. Sometimes you can cut to the chase by smelling the flowers or leaves, but if you can recognize a plant’s scent then you’re probably already familiar with it in other ways.
The yarrow plant has very highly divided leaves. The leaves are soft to the touch and arch over instead of being erect. The fern-like leaves are probably how most people would identify yarrow, instead of using its smell.
Yarrow that was transplanted into a flower bed has flourished into many plants from the original few. Note the foliage in the image above, taken 2 May 2010.
Flowers and leaves share the same stem. Yarrow flowers seem to be formed early and rise up higher as more leaves continue to develop. When the plant gets 1 – 3 feet tall the blossoms will be fully formed into a slightly rounded cluster of what appears to white, five petal flowers. The flowers are actually composite flowers with only a few broad ray flowers, most often five of them.
Two photos of yarrow flowers taken 31 May 2010.
Yarrow is a plant that is used widely in flower gardens and in fresh-cut and dried flower arrangements. White is the original, native flower color, but other colors have been propagated.
Peterson’s Edible Plant Guide