Yarrow: An All-Around Plant for the Lay-Around Gardener
Mar 28, 2019
Boy, do we have a special treat for our work-weary, lazy, or black-thumbed gardeners with "here be dragons" backyards. Yarrow is among our most forgiving, easy-to-grow, versatile ornamentals. No worries about amending crappy soil, dragging hoses around all summer, or hunting down aphids and whiteflies! No need to find counter space for seed trays among your dirty dishes, unopened mail, and empty wine bottles! These graceful plants will make it look like you slaved in the dirt for hours when in reality, they're the gardener's equivalent to microwave popcorn.
No time to run to the ER when Junior amputates his finger on the tuna can lid? Just chew up some yarrow, spit it on his owie, and let your precious three-year-old go back to making his dinner! Worried that your stress levels will kill you before you can experience one last spring? Yarrow is an early and all-season bloomer; even if you keel over from exhaustion when your kids go back to school, you'll have plenty of flowers for your funeral!
Yarrow in your garden
Yarrow is a multi-purpose plant, world-renown for its healing properties as well as for its attractive flowers and foliage. Its dense, spreading rhizomatous root system serves as erosion control along banks and disturbed hillsides, and yarrow is often used in permaculture to absorb excess rain runoff.
Are you hoping to fend off biting insects while encouraging pollinators? Yarrow attracts hundreds of butterfly, bee, and beneficial wasp species, and it's a tried-and-true ingredient in DIY bug repellent recipes. Deer won't touch it, either.
Yarrow may look like Queen Anne's Lace (Daucus carota), but as a member of the daisy family, it has compound flowers arranged in a more uniform pattern, where D. carota's simple flowers are arranged in clustered umbrels. It's difficult to imagine leaves more delicate than those on a Queen Anne's Lace plant, but yarrow's leaves are more finely-lobed, giving them a more feathery look. Also, D. carota leaves attach to the stem in an opposite pattern; yarrow has alternate leaves. Thanks to their contrasting flower patterns but similar silhouettes, Queen Anne's Lace and yarrow look gorgeous when planted together or used in the same floral arrangements.
Yarrow grows upright from basal rosettes on tall, ribbed stalks. At the top of each stalk, individual branching stems hold aloft flat, oval bunches of 2" to 4" coryms (clusters) of up to two dozen 1/4" compound flowers. Each tiny flower has four to six stubby, round-to-oval ray florets—what we'd recognize as petals—that are grooved at the outer edges, and which appear to have three pillowy ridges. At the center of each blossom are up to two dozen disc florets, each with prominent, bright gold reproductive organs. If you allow the flowers to fade, the oblong fruit pods will attract hungry birds.
Okay, let's zoom back out a minute. But still, look closely: Each segment on the frothy, 2" to 6" leaves are themselves deeply-pinnate, creating a delicate, feathery appearance. The lush foliage has a somewhat spicy and pleasing fragrance.
Now, back to the broad strokes:
- USDA Hardiness Zones: Herbaceous perennial in zones 3 through 9.
- Sunlight Preferences: Full sun, but tolerates some shade.
- Moisture Requirements: Does well in dry soil, but blooms best with about an inch of water each week.
- Soil Preferences: Prefers poor to average soil. Provide good drainage, and add sand to compacted soil. It has a wide pH range between 4 and 8.
- Plant Height: 12" to 36" tall.
- Plant Width: 18" to 24" wide.
- Growth Habit: Upright, branching only at the top.
- Bloom Period: Early spring through fall; takes a mid-summer break in the hottest regions.
Yarrow is a perfect addition to casually-scattered prairie wildflower landscapes, though it's more than presentable in cottage gardens and semi-formal beds. Yarrow adds depth to backgrounds and softens up areas planted with coarse-featured species. Grow it along veggie and herb garden fences, near outdoor dog water dishes and birdbaths, or in other areas where mosquitoes usually congregate.
In spite of its ability to thrive in dry soil, yarrow adapts well to regular moisture as long as it's not planted in overly-rich beds or standing water.
But wait! There's more! Yarrow is incredibly easy to grow from seed! If you order today, you'll also get to enjoy its rich cultural history, its medicinal properties, and the ability to create your own stunning floral arrangements at no extra cost!
Yarrow's geographical roots
Indigenous to Europe and Asia, colonists brought Achillea millefolium with them when they came to settle North America. But surprise, surprise! It was already here long before they arrived, possibly having crossed the Bering Land Bridge roughly 20,000 years ago. The ethnobotany fans at Native Languages of the Americas and wildflower conservation experts agree that the common yarrow that exists today is a hybridization of Old World and native species. According to the NLA website, many ancient indigenous languages include names for yarrow—none of them being derivative of European labels—indicating the plant was well-established in pre-Columbian times.
These are a few of the common (okay, a few are kinda out-there) names applied to common yarrow:
- Boreal yarrow
- California yarrow
- Bad man's plaything
- Giant yarrow
- Coast yarrow
- Western yarrow
- Pacific yarrow
- Carpenter's weed
- Hierba de las cortaduras
- Nosebleed Plant
Some of the names are obviously regional, but botanists agree that globally, there are so many subspecies resulting from hybridization—without significant impact on the plant's appearance, environmental preferences, and chemical compounds—that it's easier to simply file them all under A. millefolium and call it a day. We'll get to Achillea later, but millefolium means "thousand-leafed," reflecting the plant's feathery foliage.
So to sum it up, here in the US, common yarrow is classified as a wide-ranging North American wildflower, making itself at home in fields, ditches, pastures, and meadows across the continent. It's just as ubiquitous in the Old World, from the Mediterranean through Europe and Asia. Yarrow's most notable boundaries are the equator, the Arctic circle, and elevations above 3500'. If you're pretty sure you live within this range, and you can't get it to grow in your backyard, get out the Geiger counter, start taking those potassium iodide pills and call a real estate agent. You've got bigger issues.
Yarrow's medicinal and practical uses
The Native Languages of the Americas website has this to say about Achillea millefolium:
Yarrow also has a more important and longer-standing role in traditional Native American herbalism than do more recent herbal arrivals like dandelions and chicory … used as a poultice for wounds and a treatment for headaches, toothaches, and gastrointestinal problems. Yarrow is considered one of the Sacred Life Medicines of the Navajo tribe, and was sometimes burned as a purifying herb by the Anishinabe tribes.
The leaves, stems, flowers, and roots contains Achilleine, a blood-clotting alkaloid named for the genus which, in turn, is a nod to Achilles. According to legend, he used it to heal his wounded soldiers.
Many cultures ate raw or cooked yarrow leaves or, perhaps for relaxation, smoked various parts of the plant. To this day, it's used to flavor soft drinks and make dyes. You can make yarrow tea as a clarifying hair and skin rinse, or spritz it on your skin and clothes to repel mosquitoes, fleas, and ticks. In the garden, yarrow repels beetles and other insect pests, and its leaves and stems help kick-start compost piles.
Sensible precautions when using yarrow
In spite of its long track record as a healing herb, yarrow is potentially (though marginally) toxic: the same pyrrolizidine alkaloids that give yarrow its healing properties can also cause problems over time or if ingested in large quantities. Grazing herbivores are susceptible to poisoning when they're confined to pastures with a high percentage of yarrow, but browsing herbivores such as goats, deer, and primitive sheep breeds are selective feeders and tend to avoid the astringent taste.
So do pets and small children. Its prolonged internal use has cumulative adverse effects on humans and small animals, but it's unlikely that your dog, cat, or child would eat enough of the bitter plant to be in danger.
Plants for a Future (PFAF) suggests that yarrow might boost the properties of other sedative drugs and herbs, so lay off the benzos and use caution when garnishing your bevvies.
Growing yarrow from seed
There isn't much you need to do to prepare your garden when growing yarrow from seed. It's a good idea to dig in some aged compost, or even just a little garden sand, to break up compacted soil and improve drainage. Too much nitrogen will actually hurt your plants, causing them to get leggy and lodge. Wind and heavy rain can flatten them, also. There isn't much you can do about the rain but choosing a spot with a natural windbreak will keep your yarrow from looking as floppy as you do after coaching a weekend-long T-Ball tournament.
Don't bother starting them indoors. They don't need a head start, and they aren't particularly thrilled about being transplanted.
- Seed Treatment: None required.
- When to Plant Outdoors: Immediately after the last spring frost.
- Seed Depth: Surface sow; yarrow seeds need some sunlight to germinate.
- Seed Spacing: Sow or thin 12" apart.
- Days to Germination: 7 to 21 Degrees at 65°F.
If you do choose to start your seeds indoors, grow them in tall peat pots 4 to 6 weeks before the last spring frost. Place them in a sunny window, and keep the soil moist with a mist sprayer.
Pests, diseases, and maintenance
Yarrow isn't prone to pest infestations, but high humidity and wet soils can cause root rot and leaf fungus. If the blooms begin to dwindle due to midsummer heat, or they've taken on a chaotic, tangled look, cut the plants back by 2/3 and give them an extra watering for a week or two to encourage regrowth and continued bloom.
The Missouri Botanical Garden suggests yarrow as a low-traffic lawn substitute or flowering ground cover that you can cut with a rotary mower. The mower must have a drink holder and a high-cut setting to be effective.
Harvesting yarrow for floral and herbal use
Cut yarrow early in the day after the dew has dried up, snipping them at the base of their stems. Take a bucket of warm water with you so you can immediately immerse the stems for a two-hour soak. Afterward, remove the leaves (they quickly wilt) and re-cut the stems underwater before creating your floral arrangement. Use your favorite algae-preventative floral preservative, and change the water every other day.
Yarrow is an excellent dried flower, and you can harvest and dry them for medicinal purposes. Dig up the entire plant at full bloom and hang the stalks and flowers upside-down in a well-ventilated room out of direct sunlight. Brush the soil off the roots (don't wash) and dry them in a warm oven or on a screen tray, then store them whole in a dark, dry, cool cupboard until you're ready to use them.