Planting Edmonds: Lichen in the garden

Bright yellow slime mold and lichens on decaying branch. (Photos by Lora Hein)

Planting Edmonds is a monthly column written by and for local gardeners.

Like me, you may be eagerly noticing fresh green poking through what we might hope is the last snow of this winter season. Colorful buds are beginning to open on azaleas and rhododendrons. The spring garden party is about to explode like a paint ball frenzy all over our garden-rich town.

Along with buds, unfolding foliage and bright blossoms, other garden residents are returning — birds, bees, bugs, butterflies and bunnies. We may welcome some and dread others, among them the hungry slugs, gophers, moles, squirrels and raccoons. One garden resident is present all year round. This quiet participant is neither plant nor animal, but in a class entirely to itself.

Before the warm-season whirl of garden activities and summer garden parties begins, as we get outdoors to do the trimming we put off, waiting for a sunnier day, there is still time to celebrate the garden introverts. At the fringes of a gathering, these residents hang back on the sidelines while more flamboyant extroverts get all the attention.

The lichens in our gardens may be overlooked, uninvited guests. They require little to no attention or work on our part. Meanwhile, they arrive almost invisibly, take their time to be noticeable, and when they do get recognized, may be falsely accused of causing harm. It is a common misconception that lichens cause a tree to deteriorate or die; instead, they are healthy for your garden and support wildlife. Don’t be too quick to throw out those lichen-covered branches or scrape your fences.

Lichens take a very long time to grow. When we see them on old stones or trees, it is because they have had ample time to get big enough to become visible. When there are no leaves obscuring their presence or when a branch dies, lichens have greater access to sunlight.

The storms of this past winter have brought lichens growing up high all the way down to ground level. When I walk in Yost Park, I have been amazed at the abundance of lichens on downed branches on the sides of the trail. You may have had a chance to get acquainted with lichens in your own garden that are usually too high to see close up.

So, what are these fluffy, fringed, mostly gray-green colored garden residents, and why care for them?

Their relatives have been on the planet longer than most garden elements except stones. They even play a role in breaking stone into soil, a process we are not likely to observe in the span of a human life.

Crustose, like a crusty splotch on a surface, stone, or wood.

At the warming edge of the wet season, fruiting bodies of the web of mycelium, the fungal network that connects every plant in our garden with others in an underground telegraph system, appear as slime molds on dead material or mushroom caps popping up through the soil. And it’s hard to avoid the green slime that makes walkways and decks slippery and paints your fence a color you never intended.

These two cousins of lichens are relatives of the two components, a fungal and an algal partner, that combined create a new being, different from what either would be alone. Neither partner can sustain life without the other.

You may be surprised to learn that Beatrix Potter, the beloved author of the children’s classics Peter Rabbit, Squirrel Nutkin and Jemima Puddle-Duck, was also the first person to determine that lichens were a symbiotic organism. Each of the parts contribute to and depend upon the other for survival. The fungus portion provides structure, protection from drying out, and attachment to a surface — a secure foundation. The algae produce food for both. With no roots to draw water from the substrate, all the moisture the pair requires is derived from the air.

Their simple needs and ability to withstand extreme temperatures and desiccation for long periods enable lichens to grow from high in the Himalayas to the depth of Death Valley, from the equator to Antarctica.

There are three main growth forms of lichens: the crustose adheres closely to the surface it grows on. The foliose form is leafy and lifts away from the substrate but may be attached at several points. Fruticose is pendant, attached at only one point, and forms threadlike tangles.

Foliose, leafy, example: Lobaria, or “lungwort,” one of the most sensitive to air pollution, is hard to find in our area.

Lichens are great indicators of air quality. Because they derive their food from sunlight and air, they are great filters, but this filtration puts them at risk of succumbing to pollutants. Where air is clean, they thrive. However, an overload of toxic fumes can reduce them or kill them off. The next time you find yourself among ample lichens, take a deep breath, confident the air near them is cleaner than elsewhere, and allow the humble lichens to continue doing that vital job.

Fruticose, thready, dangling from their attachment point: Usnea sp. is used to dye fabrics such as the famous Harris tweeds.

In addition to cleaning the air, lichens provide food and nesting material for the creatures that share our gardens. Several of our local lichens can provide food for humans, and some have medicinal qualities. Nibbling on a few threads of an Usnea sp. may be beneficial; however, owing to the lichens’ filtering capacity and their unique acids used in pharmaceuticals, it is essential that you soak and leach them properly before you eat them in any quantity.

This winter, when taking supplements to support healing from minor surgery, I discovered that the vegan vitamin D3 and collagen chews I found both contain lichens. Beer makers use them to ferment their brews, and many medicated lotions have lichens in them. They are a primary food source for caribou and reindeer, so no lichens, no Santa’s sleigh! Without lichens, General Washington’s troops may not have survived to cross the Delaware.

Fruticose/branching foliose, between the first two: Evernia prunastri, commonly known as “perfume lichen” — components used in fine perfumes.

While the local nursery may not carry a selection of lichens to add to the diversity of your garden, there are ways you can encourage them to grow. When you clean up fallen debris from winter storms, choose a few fluffy lichen specimens to tuck into the crotch of a tree or lay along the back board of a neighboring fence. Lichens are capable of propagating from fragments. You can crumple a dry lichen, mix it with a moist substance, and sprinkle it on a fence, wall or stones; it might adhere and grow, though remember, it can take years to see visible results.

Take heart in knowing these “seedings” provide not only pleasures to enjoy when the garden repast has faded, but they provide sustenance and nesting material for garden creatures struggling to survive in the changing climate.

Caught up in the gardening frenzy of blossoms and berries, foliage and leafy greens, floral displays and fruits of the harvest, you may forget to notice lichens quietly holding their own, biding their time. Make a note, though: Once the colorful fall foliage has fallen and the flower beds are prepped for the encroaching cold, the lichens come into their own. When the big show is over you can still these appreciate these backstage mainstays for their beauty as well as for their many gifts.

If you would like to know more about the lichens of our area, an excellent resource is Macrolichens of the Pacific Northwest by Bruce McCune and Linda Geiser. A YouTube video by Linda Geiser gives an excellent overview of how lichens vary in response to. different conditions through the Columbia River Gorge:

— By Lora Hein

Lora Hein has been gardening in Edmonds for eight years. She discovered her love of lichens when she was hired as a Lichenologist for a research project sampling lichen distribution around geothermal energy plants between Napa and Sonoma, California while she was earning her degree in environmental studies and biology at Sonoma State University. She landed in Washington the following year as a backcountry ranger with the North Cascades National Park. After seven summer seasons with NOCA, for the next 30 years she cloned rhododendrons, designed passive solar homes, instructed aerobics, inspected air pollution control, managed Upward Bound, taught elementary school, and became a UniServ field representative for public education employees, from which she recently retired. She joined the Edmonds Floretum Garden Club as soon as she moved to Edmonds. Retirement has provided Lora time to write and garden. In 2018, she and her spouse, Nora Carlson, received the Snohomish Conservation Districts Conservationists of the Year – Urban and Suburban Homeowners Award. Lora gave a talk on Liking Lichens” at Floretums November 2022 meeting. Besides her love of vascular plants and nature in general, Lora still has a soft spot for lichens and enjoys greeting her old friends by name when she finds them!



  1. What a wonderful article. I also watched the video suggested on You Tube. My garden has been growing for 32 years now. The fencing around the property is covered with Lichen. I wondered if I should remove it years ago but I decided as my father had lichen too and he said “oh I don’t stain the fences or scrape the lichen, I love the way it looks.” So I followed his advice and have not scraped. After reading all this today I braved the cold and went out for inspection. There is healthy looking lichen everywhere. Even the stringy kind. I am back and my nose is cold but it was a wonderful experience seeing what my 32 years of not using insecticides or polluting my garden gave to me. I don’t burn wood or use charcoal here and I think from what I just inspected the air above and in my yard is very good. No reddish insight and well its amazing! I am very excited. Thank you for this great article.

    1. Deborah Arthur, I am so glad you appreciated the article and watched that video. It is rich with far more information than I could include in this article. I also appreciate your conscientious guardianship of air quality. Wood smoke can be very damaging. London is currently experiencing terrible air quality as a result of residents switching from oil or gas to burning wood to heat their homes. England was one of the first places where the connection between polluted air and damage to lichens was recognized.

      1. Hi Lora, I did so much. I went again today and found more new true lichen its fresh and nice. As far as using for a medium maybe a tiny piece or two very small now haha. It could be dried in a container with oris root powder. Although it would lose the color or fade it it could be painted. BUT I do not encourage removing any lichen unless there is sooooo much. I have a perfect Rose that I did this with Oris root power must have been 20 years ago and it is still ok. Very delicate but it was a special time and my husband bought roses for me so I kept that one. I cherish it. I want to join the Club Lora? Is there room for me? Deb.

  2. Very interesting! We have an abundance of lichen on our property, and we like it. I have been wondering about using some in an art application. I have been hesitant because I imagine it will wither and shrivel up, plus lose it’s color and pleasing form. Now you’ve got me thinking about doing a little test piece. Thanks Lora for a great article.

    1. Brooke Baker,
      My cover photo on Facebook is of some wall art I found at a retreat center. I don’t know how long it had been there, but it appeared to have stood up to the test of some time. We have had a cluster of lichens as a centerpiece on our table for several months now and while they are a little more shriveled than they would be in the moist outdoors, they are still lovely. They may not stand up to being attractive long term, depending on how they are included. Certain lichen species in deserts withstand decades of drought and will perk up and resume their lives when they have access to moisture. I would love to know how your art idea pans out.

      1. Ms. Hein, this is a great informative well written article. The pictures are very helpful as we have several lichens pictured. Always wondered if they are friend or foe. Now we know! Nice job!

Leave a Reply

Your email address will not be published. Required fields are marked *

Real first and last names — as well as city of residence — are required for all commenters.
This is so we can verify your identity before approving your comment.

By commenting here you agree to abide by our Code of Conduct. Please read our code at the bottom of this page before commenting.