How to Care for a Yarrow Plant

How to Care for a Yarrow Plant

What does a plant need to grow and flourish? The right soil to grow in, correct amount of light, water and fertilizer, and the right growing temperature.
Gardenerdy Staff
The common yarrow can be a medicinal treasure house, or an invasive flowering pest to a garden. This perennial flowering plant, Achillea millefolium, grows between 6-60 inches tall and has a long, narrow stem on which feathery leaves grow. The flowers are a flat, mop-headed cluster of blooms, in a disc or oval form. The blooms can be white, yellow, pink or red in color, depending on the cultivar. A group of yarrow plants makes a very picturesque and colorful addition to any garden, especially as a border to a flower bed. They even attract many butterflies and wasps due to their nectar. The dried blooms can be used in flower arrangements.

Medically the yarrow plant's leaves are very useful. The yarrow herb is effective in easing colds and the flu as well as reducing the extent of inflammation and headaches. The leaves also reduce bleeding and encourage clotting, and so are used for nosebleeds and open bleeding wounds. The yarrow plant is not only aesthetically pleasing and medically useful, it is also a very easy plant to grow, requiring minimal care and attention. In fact, once you get the knack with one plant, you can easily propagate and grow more plants.

Growing and Caring for a Yarrow Plant

It may be an easy plant to care for but there are some basic factors of plant care involved in looking after a yarrow plant. Below, the various parts of how to care for a yarrow plant are tabulated.

Sun & Climate
This little plant needs a lot of sunshine. Hence it should be grown in a sunny area. The yarrow will thrive and flourish in a hot, sunny, dry climate, but will flop over and die in humid, wet and cold weather conditions. You can grow the yarrow plant in planting or hardy zones 3-8 and some cultivars of the plant will survive in zones 9 and 10. They are spring and summer bloomers but if pruned properly, can bloom once again in fall. This plant is observed to bloom between June to September.
The yarrow plant is very hardy and can survive in low-fertile, nutrient-poor soil. The soil should be dry and drain well. Sandy or loamy soils will also do. This plant will not grow in wet, soggy soil. Wet soil can also cause fungal infections in the roots of the plant. When planting yarrow seeds or saplings, strengthen the soil with compost, then plant the yarrow. Plant each seedling or seed at least 1-2 feet apart. The yarrow blooms can grow thick and dense, so this avoids overcrowding.
The yarrow plant is very drought-tolerant and does not need to be watered regularly. In fact, too much watering can cause stem rot. Only water if the soil is dry or if the plant appears wilting or brown, due to insufficient water. Young plants and seedlings will need regular watering. If you live in a hot arid climate or during summertime, the soil dries faster, so water the plant at least once in 2 days.

If grown in an area which receives regular precipitation, do not water the plant regularly. During autumn and winter, reduce the number of times you water the plant. Avoid using too much compost or fertilizer with the yarrow plant. This plant flourishes in low-quality soil and will need fertilizers only during its growing phase. If the plant grows in a rich soil, it can grow at an alarming rate and will be very difficult to handle.
Pests & Disease
The yarrow is highly susceptible to fungal infections like powdery mildew or mold. This disease causes a white or gray powder-like substance to coat the flowers which ultimately destroy the plant. The plant is vulnerable to such a disease if humid growing conditions exist, due to climate or due to overcrowding of plants.

Spray the infected plants with sulfur dust in the early morning to help the plant heal. If the plant is infected heavily and there are no signs of healing, you will need to cut down and destroy the plant. Soggy soil can cause stem rot to affect the yarrow plant. Rust is another natural disease. The yarrow plant attracts a lot of butterflies but its real pest are aphids. Inspect the leaves of the plant carefully for holes, yellowing or sticky secretions.
The yarrow plant tends to flop or fall over, especially if it gets too tall and spindly. You may need to stake such plants as they grow. Bury one end of the stake 1-2 inches away from the base of the plant, then tie the middle of the plant's stem to the stake with string or twine. Spent blooms should be removed from the plant immediately, using shears or by pinching them off. Deadheading encourages new growth and the plant may bloom again in the same year.

It is necessary to prune the plant to its stem 1-2 inches above the soil, after the first frost. If you have a large cluster of yarrow plants flourishing for some years, you will need to divide and replant them every 3-4 years. Transplant each plant, roots and flowers intact to a different location and separate them from the cluster.
You can grow more yarrow plants through seeds or cuttings. Seeds will need to germinate indoors for 1 week at 65° F. They will take 2 weeks to germinate outdoors at the same temperature. Along with temperature, germinating yarrow seeds require light. You can propagate the plant by root division or through cuttings taken from a healthy plant in spring. Yarrow plants grown from seeds, will mature and establish themselves in a year. But if grown from cuttings, they will mature faster.

As you can see from the above steps, this plant is really low-maintenance and tough. It can grow in conditions that would normally destroy any other plant. But the trouble with the nature of such a hardy plant is that it could take over the garden and turn into a weed, if not controlled and monitored by a diligent gardener.