Yellow Yarrow Varieties

Description

• Yarrows are generally 1- to 3-feet tall and wide. Flower stalks appear in summer from basal rosettes of finely divided, ferny leaves that are green or gray and are aromatic when handled. Small daisy-like flowers cluster together atop the stalk in a flattened, rounded grouping of flowers called a corymb. Members of the daisy family, yarrow species are native to North America, Europe and Asia. Hybridzers have interbred them to create many cultivars, which in turn freely hybridize. Flower colors include white, cream, yellow, pink, red, orange, salmon and mauve.

Cultivation

• Give yarrow full sun and poor soil to keep plants compact and flower stalks sturdy. Plants are drought-tolerant once established. Cut the plants back to the crowns in late winter or early spring. This is also the best time to divide the plants. Propagate named cultivars by division because they don't come true from seed. Deadhead the flowers to prolong bloom, and remove any dried fruits. When harvesting blooms for dried flowers, cut the stalks just after the individual small flowers have opened for the best color. Hang small bunches of flower stalks upside down in the shade in a place with good air circulation. The yellow-flowered "Parker's Variety" is the dried yarrow usually sold by florists.

Fern-Leaf Yarrow Varieties

• Cultivars of fern-leaf yarrow (Achillea filipendulinea) grow to 4 feet tall and are long-lived, lasting five-to-10 years. Sturdy flower stems support the flower heads without the need for staking. Finely cut green leaves produce flower clusters in shades of yellow that can be 5 inches across. "Cloth of Gold" has 2- to 4-foot long flower stalks. "Gold Plate" produces deep yellow flowers on 2- to 3-foot tall cut stems, with some reaching 5 feet. "Fine Gardening" magazine calls "Parker's Variety," also called "Parker's Gold," the most popular fern-leaf yarrow cultivar in its book "Perennials."

Hybrid Yellow Varieties

• "Coronation Gold" is a hybrid between fern-leaf yarrow and a smaller, deeper yellow-flowered species, Achillea clypeolata. This free-flowering form is more compact than fern-leaf yarrow and produces 30-to-60 flower stems per clump, frequently hiding the foliage. The bloom period lasts between eight and 12 weeks. "Great Expectations," part of the Galaxy series of yarrow, which are hybrids between Achillea clypeolata and common yarrow (Achillea millefolium), has primrose-yellow flowers. A cross between Achillea taygetea and Achillea clypeolata produced "Moonshine," with sulphur-yellow flowers held against gray ferny foliage. The "Debutante" line of Achillea taygeata cultivars has a wide range of colors, including shades of lemon yellow and gold.