Yarrow is a trouble-free plant that offers many benefits in your garden or landscape.
Yarrow (Achillea millefolium) is native to all of the temperate (non-polar and non-equatorial) regions of Earth. Traditionally, the above ground portions of yarrow, also known as the nosebleed plant, old man’s pepper, soldier’s woundwort, and thousand-seal, was used medicinally to stop the flow of blood from wounds, ease toothache, treat digestive discomfort, and to induce sweating. The science behind what yarrow can and cannot do is limited. It is a mild sedative. Some studies have shown that it can relax the smooth muscle of the uterus, so it should not be taken by pregnant women. Yarrow may also be able to intensify the effects of blood-thinning and blood pressure reducing medications, lithium, and sleep aids. Also, yarrow is believed to slightly increase stomach acid. Even if you never touch the stuff, yarrow is a good addition to a landscape. It looks nice in containers, too.
The yarrow plant
Yarrow makes an excellent ground cover. If mowed regularly, it will remain prostrate. If left to its own devices, it will grow to be a foot or two tall. The lovely feathery leaves feel soft and delicate to the touch, but these plants are tough. I don’t do anything for mine and they just keep on growing. Yarrow is drought tolerant and butterflies are drawn to the flowers.
While not particularly edible, the way lettuce or spinach are, yarrow can be dried and used to make a tea. Young leaves and flowers are sometimes added to salads, but I just tried it and don’t care for it. The tea is very nice. Yarrow has been used as livestock feed, in some regions, and to some, it is a weed. Yarrow’s true value, however, lies in its role as an insectary.
Yarrow as insectary
Increasing the biodiversity in your garden or landscape helps to keep it healthier. Mutually beneficial arrangements that have taken millions of years to sort themselves out really are effective. Rather than trying to Disnefy your landscape, with neat and tidy arrangements, adding a variety of flower shapes, sizes, and colors will attract more beneficial insects. Okay, okay, so we all want the topiary elephant, but diversity is still healthier than monoculture. Yarrow flowers provide nectar and pollen to many beneficial insects, including:
Aphids, striped and spotted cucumber beetles, flea beetles, and lygus bugs are also attracted to yarrow, but, in this case, that’s a good thing. First, it means they are not on your tomatoes. Second, those particular aphids are destined to be eaten by the larval forms of all those beneficial insects! Sort of a hoverfly happy meal!
Yarrow seeds need light to germinate, so do not bury them in the soil. A light dusting of soil or vermiculite will hold the seeds in place, but you might want to use a mister to water the seeds until the germinate. Either that, or you can saturate the soil with water, add seeds, and cover with plastic until the seeds germinate. Once your yarrow gets going, you will want to find it a permanent home. Yarrow tends to spread on its own, and it can even be used as a low border hedge. You can easily dig established plants up and divide them.
In the Bay Area, it is all too common to have areas of bare, hard-packed clay. This encourages erosion and unhealthy soil. Adding yarrow to your landscape or garden is a good way to reduce erosion, attract and feed beneficial insects, and hey, the flowers are lovely, too!
You can grow a surprising amount of food in your own yard. Ask me how!