Yarrow (Achillea millefolium) is a resilient perennial plant valued for its feathery foliage and vibrant flowers. Propagating yarrow is a straightforward process, allowing gardeners to expand their displays or share plants. This adaptable herb is easily multiplied through several common methods.
Propagating Yarrow Through Division
Propagating yarrow through division is particularly useful for rejuvenating older, established clumps. This process is best undertaken in early spring as new growth emerges or in the fall after the plant has finished flowering. Division helps maintain plant vigor and prevent overcrowding.
To divide yarrow, dig a circle 6-12 inches around the plant’s root zone with a shovel or spade. Carefully lift the entire clump, noting that yarrow roots are shallow. Separate the root ball into smaller sections, ensuring each new division has a healthy mass of roots and at least three to four stems or shoots. Use a sharp spade or an old kitchen knife for this task, cutting through the fibrous root system.
Replant divisions promptly into their new locations at the same depth they were previously growing. Space newly planted sections 1 to 2 feet apart for future growth and air circulation. Water replanted divisions thoroughly to settle the soil around the roots, eliminate air pockets, and promote successful establishment.
Propagating Yarrow From Cuttings
Propagating yarrow from stem cuttings offers a reliable way to create new plants, yielding quicker results than seed propagation. Softwood cuttings, taken from new growth, are most successful. The optimal time for taking cuttings is late spring to early summer.
Select healthy, non-flowering stems 4-6 inches long. Use sharp pruners or scissors to make a clean cut just below a leaf node, where leaves attach to the stem. Remove leaves from the bottom half of each cutting to expose these nodes, as new roots emerge from these points.
Dipping the cut end into rooting hormone is optional but can encourage root development and protect the cutting. Insert prepared cuttings into a well-draining rooting medium, such as peat and perlite or sand. Ensure exposed nodes are buried. Keep the soil consistently moist but not waterlogged, and place cuttings in a bright spot out of direct sunlight. Creating a humid environment, perhaps with a plastic dome or bag, aids in rooting.
Propagating Yarrow From Seed
Growing yarrow from seed is a cost-effective method, allowing for a broader range of plant characteristics. Seeds can be sown indoors in late winter to early spring or directly outdoors after the last frost. Starting seeds indoors 8-10 weeks before the last expected frost can provide a head start and potentially lead to first-year flowering.
When sowing seeds, use a well-draining seed-starting mix in trays or containers. Yarrow seeds require light for germination, so sow them on the soil surface and press lightly to ensure good contact without burying them. A thin layer of vermiculite can cover the seeds and help retain moisture.
Keep the seed-starting mix consistently moist, watering gently to avoid disturbing tiny seeds. An ideal soil temperature for germination is 65-72°F (18-22°C); a heating mat can speed up the process. Germination occurs within 10-14 days. Once seedlings develop their first true leaves and are large enough to handle, they can be thinned or transplanted.
Caring for New Yarrow Plants
Proper care for newly propagated yarrow plants is important for successful establishment. New yarrow plants require consistent moisture during their initial growth phase. Water deeply once a week if rainfall is insufficient, but avoid overwatering, which can lead to root rot. Once established, yarrow becomes drought-tolerant and requires minimal supplemental watering.
Yarrow thrives in full sun, needing at least six hours of direct sunlight daily for optimal growth and abundant blooms. Placing young plants in a location with ample light helps them grow compact and strong. Poorly drained or overly rich soil can cause yarrow to grow leggy and less robust; well-draining, lean soil is preferred.
When transplanting young yarrow plants to their final garden location, select a site that accommodates their mature size, 1-3 feet apart. The best time for transplanting is mid-spring to early summer. Dig a hole 1.5 to 2 times the size of the root ball and plant at the same soil depth as in its original container. Providing a layer of mulch around the plants helps conserve moisture and suppress weeds as they establish.