Coronation Gold (Achillea ageratifolia) is a beautiful tall-growing variety of Yarrow, a perennial herb that lights up my pollinator garden from June through August. I find the metamorphosis of the Coronation Gold flower so fascinating. In the early stages of bloom, the flower head looks like a tiny cauliflower. Over the course of several weeks, the tightly packed flowers gradually open up and flatten out like a small saucer. While the dramatic change in shape is happening, the color of the flower is also transitioning from pale white to a stunning, mustard-yellow color. I wish I had Coronation Gold planted all around my garden, hence the reason why I am harvesting seeds this week.
The early blooms look like baby cauliflowers to me.
Coronation Gold blooms just a few weeks later
The blooms gradually open up and flatten out. Each flower head is actually a cluster of small blooms. Apart from being visually striking, Yarrow is a very easy plant to grow and will attract lots of bees and butterflies to your garden. It grows best in full sun and well-drained soil. Yarrow is also pest (including deer) and drought resistant. My plant is about 2 feet tall and 4 feet wide.
Coronation Gold flower heads left to dry in the garden
Resist the urge to deadhead Yarrow blooms once they start to fade. Leave them on the stem to set seed and dry out. As you can see in the photo above, the shape of the bloom will remain the same as it dries, but the once gold flower heads turn brown, as well as, the top portion of the stem. This change usually happens in late summer and is a sign that the seed heads are ready for harvesting. Where I live in Zone 7b, the seed heads are ready for harvest around mid August
Gently snip off the seed heads with clean pruners and drop them in a paper bag or other container. Instead of using bags to collect seeds, I like to use clear, plastic lettuce containers. It keeps them out of the landfill and the clear packaging allows me to see the seeds/chaff inside.
Give the pruned seed heads a firm tap or two to release the seeds and chaff. Lots of little seeds will fall out into the container. Yarrow seeds are tiny, so don’t worry about separating the seeds from the chaff at this point. Nature will take care of that for you during planting season. You can follow these same steps to collect seeds from other perennial flowers like Shasta Daisy, Black-eyed Susan and Coneflower.
Store the seeds you harvest in a cool, dry location over winter. They’ll be ready for planting next year.
You got this!