How to Grow and Care for Common Yarrow

Common yarrow (Achillea millefolium) is a perennial flowering plant that goes by many names, like gordaldo, poor man's pepper, and thousand leaf. In the southwestern U.S., you'll hear it referred to as a plumajillo, Spanish for "little feather," due to the feathery shape and lacy texture of the plant's aromatic leaves. Yarrow can grow to reach more than 3 feet tall during a growing season, and it bears an umbrella-like canopy of clustered mini blooms on long, slender stems. Plant this herbaceous perennial in the spring, and come summer, you'll be graced with little white flowers.

Common yarrow is commonly seen growing across the United States in dry, disturbed soil, and while its beauty is delicate, the plant is also considered an aggressive weed. Common yarrow can be toxic to dogs, cats, and horses, yet poisoning is rare, as the tannins in the plant give it a bitter taste that detersanimalsfrom overconsumption.

Common Yarrow Care

Drought-tolerant common yarrow grows well in poor soil, making it an ideal plant for xeriscaping, especially if you live in a desert environment. Yarrow is most often sold as plant starts, but it can be easily grown from seed and doesn't need much attention once established. Simply make sure to plant it in soil that is well-drained, watering it regularly during drought conditions but giving it ample time to fully dry out in between.

While this plant is technically considered invasive only in noncultivated settings, common yarrow still needs to be planted in an area where you don't mind proliferation.

Light

Yarrow prefers a garden plot that receives full sunlight, as these conditions will help it stay compact, yielding many blooms. This plant can tolerate partial shade, yet inadequate sunlight may cause it to grow long and spindly, requiring staking.

Soil

Common yarrow can adapt to a variety of soil compositions, from sandy to loamy to clay. Still, whatever the medium, this plant grows best in dry, well-drained conditions. Avoiding fertilizer or compost is often suggested, as nutrient-rich soil will encourage aggressive, and possibly unwanted, growth.

Water

Once established, common yarrow is drought-tolerant. Frequent, light waterings will only be needed to encourage germination and to mature small seedlings. After that, only a 1/2 inch of water weekly is needed to maintain growth. During periods of natural rainfall, cease watering altogether, especially if you're getting up to or more than 1 inch of water per week.

Temperature and Humidity

Yarrow thrives in warm, summer conditions, with temperatures of 65°F to 75°F, but can start to suffer heat damage if temperatures rise over 86°F. Yarrow does not like cold drafts or temperatures near freezing.

Yarrow can tolerate some humidity, but prefers conditions dry and may fall victim to root rot or fungus if its soil becomes saturated.

Fertilizer

Yarrow plants are low-maintenance when it comes to feeding. An annual side-dressing with compost in the spring should be enough to last throughout the season. However, some gardeners choose not to fertilize this plant at all, as nutrient-rich soil may encourage invasive spread.

Types of Common Yarrow

In the wild, yarrow typically blooms in lace-like shades of white or cream, but cultivated yarrow comes in many colors, like yellow, purple, pink, and red. Below are a few gardeners' favorites:

• 'Apple Blossom' syn. 'Apfelblute' is cross between A. millefolium and A. taygetea. This variety features purplish-pink flower crowns that are 2 to 3 inches wide.
• 'Cerise Queen' grows deep pink flowers and dark green foliage. The stalks of this cultivar reach 1 to 3 feet tall at maturity.
• 'Little Moonshine' is a compact variety that only grows to 9 to 12 inches tall. It works well in containers and features bright yellow flowers and silvery-green leaves.
• The stalks of 'New Vintage Red' grow 12 to 15 inches tall and bear vibrant red flowers and bright green leaves.
• 'Paprika', a galaxy hybrid, grows brick-red flowers that are 2 to 3 inches wide with clusters of bright red flowers that eventually fade to shades of pink when the plant reaches maturity.

Pruning

Yarrow needs regular pruning and deadheading in order to keep the plant in a state of continual bloom. Plant stems can grow long in a hot, humid climate, and may require cutting after flowering to reduce plant height and to avoid flopping. Habitual pruning will also help keep the plant in check by preventing self-sowing.

Propagating Common Yarrow

In ideal growing conditions, yarrow spreads rapidly and sometimes aggressively. For this reason, it's best to divide the plant every two to three years or as needed. Propagating yarrow by division allows you to relocate the same variety to a different area of your garden, or you can give it to friends looking for additions to their perennial beds.

Here's how to propagate yarrow through division:

1. Gather a spade, gardening gloves, and compost.
2. In the spring, just as new growth starts to appear, use your shovel to loosen the soil around the plant.
3. Cut the root ball in half with your shovel, and divide one half into the desired number of segments, making sure each one has three, or more, stems attached.
4. Add the segments to your garden by digging holes spaced 1 to 2 feet apart and deep enough to accommodate the segment's root ball.
5. Add compost to the hole and mix it into the soil.
6. Place the plant in the hole, ensuring the top of the root ball is flush with the soil line. Backfill the hole with a soil and compost mixture. Water thoroughly.

How to Grow Common Yarrow From Seed

Yarrow also proliferates easily from seeds sowed in the early spring. In approximately 120 days (three months), your plant will bear breathtaking blooms.

Here's how to plant yarrow from seed.

1. Gather a seeding tray, seed-starting medium, and a heating pad (optional).
2. Sow the seeds indoors about eight to 10 weeks before the last predicted frost by distributing them over a tray filled with starting mix. Yarrow needs light to germinate, so sow the seeds on top of the mix—do not cover with soil.
3. Press seeds firmly into the mix. Water until moist.
4. Place the tray in a warm, sunny window indoors and add a heating pad to the bottom of the tray to help speed germination (optional). In about 10 to 14 days, the seeds will begin to germinate.
5. Harden off seedlings by placing the tray outdoors during the day for a week before transplanting them into your garden.

Perfect for Cutting Gardens

You may find common yarrow seed included in wildflower mixes that, once planted and mature, make a great option for a cutting garden.

Potting and Repotting Common Yarrow

Common yarrow grows tall—some varieties can reach up to 40 inches. To accommodate its growth in containers, you'll need to use a large pot or choose a dwarf variety. Yarrow grows best in a porous clay or terracotta pot that drains and dries easily. Any standard potting soil will do, but make sure it contains perlite for good drainage.

It's best to use plant starts when growing yarrow in pots, as you'll get a jump on maturity and blooming. To do so, fill your pot with potting soil, dig several holes in the soil, and place a start in each one, allowing space in between. Water the pot thoroughly and allow it to drain, and then place it in a sunny patio location. Once established, make sure the soil dries out completely between waterings.

Overwintering

In late autumn, when the temperature starts to drop and your yarrow plant loses its vitality, cut the plant back to its basal leaves. The basal leaves will protect the aboveground parts during the winter, and the act of pruning will allow the plant to focus on its root system during its period of dormancy.

Common Pests & Plant Diseases

Common yarrow may become susceptible to botrytis mold and powdery mildew—both of which will appear as a white powder on the leaves—if its roots are saturated with water. Improving soil conditions and airflow between the plants, as well as plenty of sunshine, can reduce the infection.

Spittlebugs can also move into a patch of yarrow. This infestation will present as specks of "spit" on the plants. If the number of bugs becomes overwhelming, use a strong spray of water from the garden hose to reduce the population and to remove the coating from the bugs. This will expose the bugs to the sun, eventually killing them.

How to Get Common Yarrow to Bloom

Yarrow is a late bloomer, often showing its color in August in most growing regions. Ample sunlight and near-perfect soil conditions will assure a successful bloom. Once the plant starts blooming, constant deadheading will keep it in a continual state of color. Fertilization is not recommended to enhance yarrow blooms but will only cause the plant to spread rapidly and produce more greenery.

Common Problems With Yarrow

Overwatering is the most common issue with this extremely drought tolerant plant, as roots soaked in water may rot, or fungus may move into the plant. To avoid this, always plant yarrow in well-drained soil and stick to the suggested watering schedule. Avoid watering this plant during periods of rain.

When grown in gardens without direct sunlight, yarrow stalks may become long and need staking. That said, it is next to impossible to stake a proliferate patch of yarrow. In that instance, all you can do is let it flop to the ground.

From: thespruce