Cutting Back Yarrow – Information On Pruning A Yarrow Plant

Cutting Back Yarrow – Information On Pruning A Yarrow Plant

By: Shelley Pierce

Yarrow can be an eye-popping feature to any garden with its umbrella-shaped flower clusters that are available in a show of colors that span the rainbow. It is also an attractive plant to gardeners because it is low maintenance, drought resilient, and relatively pest free. Please keep in mind that “low maintenance” is not the same as “no maintenance.” Some yarrow trimming still needs to take place because letting yarrow go au naturel isn’t such a good idea. Let’s learn more about how to prune yarrow and why pruning a yarrow plant is important.

How to Prune Yarrow

Yarrow flowers will become faded and brown over the course of their growing season. You will want to deadhead these unattractive spent flowers not only for aesthetic reasons, but also to encourage further blooming. This deadheading, or yarrow trimming, is advocated because yarrow is an aggressive self-sower. Removing the spent blooms will prevent the yarrow flowers from drying out, going to seed, and spreading all over your garden.

Once the spent blooms are removed, energy is then diverted into creating more blower buds. Another reason for deadheading has to do with genetics. Yarrow is said to have a propensity for crossbreeding, so if you do let the plant self-sow, you might end up with plants that have reverted to their parent form, namely the wild yarrow with white-gray blooms.

To deadhead after the plant’s initial flowering, examine the yarrow stem underneath the spent cluster of blooms. Simply take a pair of pruning shears and cut the stem back above a lateral bud. It is from these lateral buds that side flower shoots are produced. When cutting back yarrow, you may want to consider pruning it back by at least half, given the plant’s propensity to be floppy and tip over.

Prune the entire stem to the lower basal foliage (the foliage at the bottom of the stem, down by the ground) after all the spring/early summer blooms are done. Cutting back yarrow will help maintain plant health and vitality, as it will encourage new growth with stronger stems with the potential for additional fall blooms. Prune back to the basal leaves again in late fall or early winter. The basal leaves will help protect the yarrow plant during the winter.

Tips for Pruning Yarrow

When pruning yarrow, you may want to consider wearing a pair of gardening gloves, as some people suffer allergic reactions from handling the plant.

Practice good garden sanitation when cutting back yarrow. Dispose of seed heads and all dead foliage in an appropriate receptacle such as a compost bin. This will help keep disease and insects at bay.

Pruning a yarrow plant can happen before the blooms are spent. Let your inner florist shine and cut some blooms of yarrow to use in flower arrangements.

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Yarrow plants can be grown in planting zones 3 to 8. In other words, they thrive across most of the United States except in extreme climates such as deserts and high mountains. The fact that a particular species and cultivar can grow in your area, however, does not mean that it is native to your area. You may want to check to be sure that the species you've selected is not an invasive that will push out other, local flora.

Once you've selected the particular type of yarrow you'd like to grow, it's helpful to know these facts about caring for your plants.

  • Yarrow plants can reach 3 feet in height with a spread of about 2 feet. These perennial fragrant plants are known for their feathery foliage and flattened flower clusters. Blooming occurs June to September. Flowers come in a variety of colors, including white, yellow, pink or red.
  • Yarrow plants grow best in full sun and in well-drained soil, but they will tolerate clay soil better than many plants. They are drought-tolerant once established.
  • Yarrow plants are especially popular as edging plants and in rock gardens. As a deer-resistant perennial, they are useful in deer control. They also make for a good cut flower.
  • Yarrow plants should be staked, or else you may find the stems flopped down on the ground after high winds. Trim plants back after flowering to encourage additional blooms. Dividing every other year or so promotes good air circulation, cutting down on problems with powdery mildew.
  • Yarrow plants spread by rhizomes and have been known to naturalize. They are considered somewhat invasive plants.

How to Care for a Yarrow Plant

Yarrow, sometimes known as sun fern for its high light requirement and fern-like foliage, is an herbaceous perennial plant valued for its aromatic, ornamental flowers. The yarrow plant can reach up to 3 feet in height and develops flat, dense clusters of flowers in spring, summer and fall. Yarrow flowers are most often white, but they can also be yellow, orange, pink or red. Yarrow plants are hardy in zones 3 through 9, and require very little care to thrive in the home garden.

Purchase yarrow plants in spring or fall from a nursery or garden center. They are typically available as started plants in 1- to 6-gallon containers. Choose a planting location that receives full sun and has well-drained soil of average fertility.

  • Yarrow, sometimes known as sun fern for its high light requirement and fern-like foliage, is an herbaceous perennial plant valued for its aromatic, ornamental flowers.
  • Yarrow plants are hardy in zones 3 through 9, and require very little care to thrive in the home garden.

Prepare the site by cultivating the soil to a depth of 6 inches with a garden tiller. Dig a planting hole of equal depth and twice as wide as the plant's current growing container. Place the yarrow plant into the hole, back-fill with soil and water thoroughly. Space plants 18 inches apart to allow room for growth.

Water yarrow plants only after the soil has completely dried, about once per week during spring and summer. Reduce the frequency of watering during fall and winter to once every two weeks, or any time the top 2 to 3 inches of soil are dry to the touch.

Remove spent yarrow flowers after they have faded to encourage further blooming. Cut back the dead flower clusters with pruning shears or pinch off with your fingers if possible. In some cases, deadheading may result in a second bloom in fall.

  • Prepare the site by cultivating the soil to a depth of 6 inches with a garden tiller.
  • Water yarrow plants only after the soil has completely dried, about once per week during spring and summer.

Stake tall yarrow cultivars to prevent them from falling over or drooping when they become too tall. Place a flower stake in the ground 1 to 2 inches from the base of the plant and secure it loosely to the stake with garden twine for the best results.

Yarrow flowers may be cut for flower arrangements if desired, and this will have the same effect as deadheading.

Divide yarrow plants once every 2 to 3 years to increase vigor and prevent the plants from becoming too crowded.

No supplemental fertilization of yarrow plants is required. Blooming and longevity may suffer if the plants are fertilized.

Do not apply water to yarrow plants on weeks that receive at least 1 inch of natural rainfall. Yarrow cannot tolerate soggy soils, and too much water can result in weak plants prone to fungal diseases.

Foraging for Wild Yarrow

Yarrow, mountain mint, dandelion, willow, plantain, chickweed, calendula, and chamomile all offer stellar medicinal benefits. These common woodland plants are but a few of the wealth of medicinal plants found in Mother Nature’s medicine chest.

However, yarrow stands head and shoulders above the rest. Medical research studies conducted on yarrow confirm the plant’s impressive antioxidant, antiviral, antibacterial, and anti-inflammatory properties.

Bureau of Land Management Oregon and Washington / Flickr (Creative Commons)

In the United States, wild yarrow is most plentiful in areas with mountainous terrain. The entire yarrow plant proves useful. Gather stems, leaves, and flowers in late summer when the plant is in full bloom.

When wild harvested, plants such as yarrow are used as the primary herb or infused together with garden herbs and essential oils in a creamy herbal ointment. This ointment helps bring healing relief to dry, rough skin and chapped lips, muscle pains, cuts, insect bites, and allergy irritations. Talk to your local county extension agent for assistance in identifying wild medicinal plants native to your local area.

Down to Earth: Dividing the Yarrows

Many times, I have turned unannounced visitors away with ­regret, but this couple had come so far that I didn’t want to disappoint them.

Early spring, when perennial herbs are just coming out of dormancy, is the ideal time to divide and renew them. Yarrow, mint, oreg­ano, thyme, comfrey, lamb’s-ears, mo­narda, echinacea, and lemon balm are among the many herbs that benefit from being divided every three to four years. Dividing herbs gives me the opportunity to remove them from their growing beds and spend some time improving the soil. In late February and early March, when temperatures fluctuate between 10° and 60°F, I till the soil deeply, working in compost and sphagnum peat. I don’t divide lavender or sage, but even these herbs benefit from being lifted so that the beds may be tilled. I renew each herb bed every few years.

One warm and pleasant late winter day, I was dividing my yarrow, humming as I lifted each plant with a potato fork, cut the root-bound clumps into several divisions with an old, sharp butcher knife, and quickly replanted them into a newly tilled raised bed. I anticipated ending up with several times as many plants as when I started. I was interrupted at my task by the arrival of visitors.

They were an older couple from Fort Worth, Texas, who said they’d driven to the Ozarks just to visit my garden. I explained that my garden and shop are open only one day a week from May to October except for groups and advance reservations. Many times, I have turned unannounced visitors away with regret, but this couple had come so far that I didn’t want to disappoint them. I reluctantly stopped my work and agreed to give them a tour of my winter garden.

We walked along the gravel pathways and talked. As we strolled, I picked sprigs of rosemary and lemon thyme, as well as snippets from the newly emerging mints. Handing each one to the woman, I would say, “Smell and taste this.”

She tried each tiny sprig, exclaiming over how fresh and welcome it was in the still-winter air. “Here, honey,” she would say as she handed the sprigs to her husband. “Taste how good this is!”

The woman was full of excitement and enthusiasm. She asked many questions, explaining that she had a few herbs but not nearly the three or four hundred kinds I grow. Some of the plants had not yet shown any new growth, but she read the labels to get an idea of what would fill the empty spots in warmer weather.

The man only grunted. He stared off at the corners of the garden and down into the woods. The longer we walked and the more early spring herbs I handed her, the less responsive he became. I began to feel resentful of his attitude, feeling that he was showing no support for his wife’s interests at all.

After the tour, we went into the herb shop at the edge of the garden. The woman continued to display her enthusiasm, which I enjoyed. “Honey, smell this seasoning.” she said. “Shouldn’t we get some of each of these? They’re from right here, from this garden!”

The man only looked annoyed. By now, I was having to work to hide my frustration. Why didn’t he just stay in the car and let his wife enjoy herself? I thought.

The woman made her selections to purchase. She was generous in her praise of my peaceful spot of earth. As they walked away from the herb shop porch and up the path to their car, the man turned in midstride.

“I know I haven’t seemed very interested,” he said. “It’s just that there’s more here than I can begin to absorb. You obviously really enjoy your work. I have a job I detest. I only wish that someone had told me thirty years ago that it was all right to work at something I loved as you do. I really envy your life!”

With that he turned, got in his car and drove away. I had so completely misjudged his reactions. With new perspective, I went back to dividing and multiplying the yarrows.

Jim Long is an herbalist who lives and works at Long Creek Herb Farm, a modest but amazingly productive piece of land tucked away in the Ozarks above Oak Grove, Arkansas, miles from a paved road. We all envy his life.

Watch the video: How to Grow Yarrow Achillea