Achillea millefolium is mainly known as traditional medicine and ornamental crop, but it is much more useful than is commonly thought.
Fertilizing and improving soil quality
The deep and branched root system provides the plant with potassium, phosphorus and copper – yarrow makes a highly nutritious fertilizer. It is often grown in orchards to further stimulate fruiting: the plants are crushed and used for mulching fruit trees or added to compost.
While the young trees will build mass, planted between them yarrow will not only enrich the soil with minerals, but also loosen excessively dense soil. A combination of the following plants, which require almost no mowing, will have a particularly good effect:
- Italian ryegrass,
Soil lead abatement
Plants that accumulate copper also absorb lead. Even if you are sure that the site is located in an environmentally friendly area, soil analysis can show the presence of this element: lead was the basis of the old formulas of paint coatings for houses. This is why yarrow and other plants that absorb copper and zinc are specially planted in contaminated areas.
If you choose to plant yarrow to clear the earth of lead, never use it for fertilizer, medicinal, culinary, or decorative purposes! At the end of each growing season, these plants should be dug up with the root and disposed of.
Attracting beneficial insects and pollinators
The flowers are of interest to many insect pollinators, and the useful insects – lacewings, ichneumon flies, beetles, spiders, ladybugs, and hoverflies – the openwork leaves provide a hibernating and ovipositioning site. In addition, the essential oils of yarrow repel pests, and it is a good companion plant for especially pest-prone crops.
If not mowed, yarrow can reach a meter in height and bloom all summer long. However, it is also suitable as a creeping groundcover that can withstand a little foot traffic. You will only need to mow it a few times a year. You can hardly expect it to flower, but its ability to attract beneficial insects will not suffer.
The flowers, young leaves, and upper parts of the plant are widely used in folk medicine. Yarrow tea helps get rid of fevers, compresses relieve painful bruises and inflammation. The plant is also known as a first aid remedy – for example, in stopping bleeding. It also relieves itching and pain from rashes, insect bites, cuts, and burns and helps them to heal.
Leaves and stemless inflorescences are used as a spice and for decorating baked goods, but care must be taken: in large quantities they cause poisoning.
For decorative purposes, yarrow looks good in dry bouquets, flower arrangements and wreaths.