Table of Contents
What is Eco Printing?
How is Eco Printing Yarn Different than Eco Printing Fabric?
How I Eco Printed my Yarn
Supplies
Tools
Mordanting
Bundle Dyeing the Yarn
Cleaning and Finishing the Eco Printed Yarn
Using Your Eco Printed Yarn
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What is Eco Printing?
Eco printing is a natural dyeing technique that uses plants to create patterns on textiles. Depending on the technique and materials, the patterns can be anything from abstract textures to clear imprints of leaves and flowers.

One of my favorite types of eco printing is bundle dyeing. In this technique, the fabric to be printed on is first prepared with a mordant (a chemical such as alum that helps bond the color to the fibers). Next, the plants are arranged over the fabric in the desired pattern or quantity. This is then rolled up and tied into a little bundle. This bundle is steamed for an hour or so, then left to cool. Once the bundle is opened, the plant matter is discarded and the fabric washed and dried. At this point the fabric is ready to use.

How is Eco Printing Yarn Different than Eco Printing Fabric?
The main reason that it isn’t possible to use this method unaltered to dye yarn is because, unless you’re using big, intact pieces of plant, it will make a mess. Removing little bits of wet plants after dyeing is not easy, especially if you’re using a grabby wool yarn. Marigolds are one of my favorite flowers to use when natural dyeing, and their tiny petals could easily become perminantly entangled. I don’t even want to think about what a headache it would be to pick out logwood chips!

So, I realize there needed to be a barrier of some sort between the yarn and the plant materials. Something that would allow the color to seep through while at the same time keeping the plants separate from the yarn.

My solution, was cheese cloth. The weave was loose enough that there would be plenty of contact between the plants and the yarn, but it would still be easy to separate them after the dyeing process was over.

How I Eco Printed my Yarn
Below is the exact process I used to make this speckled yarn. I’ve tried to include as many details as possible, but a passing knowledge of natural dyeing and/or yarn handling will defiantly help. That said, it’s hard to go too wrong here, so don’t be afraid to try this even if you’re a beginner!

Also, I would have included more images, but at the moment I can’t take pics in the dye space I use. It’s not ideal, but I hope you understand!

Supplies
Yarn – I used Knomad Marshmallow Worsted. You’ll want this in hank format, not in a ball or skien.
Alum – For my mordant, I chose to use alum at 12% Weight of Fiber (WOF) for wool. If you’re using a different fiber you may need a different type or amount of mordant. If I’m not sure about something like that, my favorite resource is the book The Art and Science of Natural Dye by Joy Boutrup and Catharine Ellis (Amazon.com / Bookshop.org)
Dye stuff – a variety of dye materials will work. I used marigold petals (grown in my garden), hibiscus, and black mallow. Many flowers will give great colors. I adore the yellow-green you get from dahlias. You may also want to try food waste like onion skins (yellow or red), pomegranate peels, avocado skins, or expired tea. Or you can purchase dried dyestuff online. Logwood and cochineal are some of my favorite because they give such impressive results.
Cheese cloth – I recommend this hemmed cheese cloth. It’s a little stiffer and thicker than I normally think of cheese cloth, which made it much easier to work with. Plus, I was able to get most of the plants off so I could run it through the wash after, making it reusable.
String – Any undyed string will work here as long as you can tie it tightly. I tend to reach for a cotton crochet yarn.
Tools
Small scale – Ideally a scale that is accurate down to 0.1 gram. This is for measuring the weight of our fiber as well as the alum.
Large pot with a lid and steamer insert – this should be big enough to fit all your yarn with a bit of room for movement. The pot needs to be made of a non-reactive metal (stainless steel is ideal) and should never be used for cooking after it’s used for dyeing. I find that I can do one 100 gram skein comfortably in a 5 quart pot (I like to do this for sampling) and this six quart set would likely work well., but for multiple skeins I need to go quite a bit bigger. I don’t think I’d start out with anything bigger than this 30 quart set as a new dyer. I’d also suggest checking out thrift stores if you’re looking to invest in something big.
Small spoon – for measuring out the alum. You may also want a small bowl or a piece of paper to protect your scale.
A smooth plastic or metal spoon – for managing your yarn while mordanting. A wooden spoon will work in a pinch, just pay careful attention so it doesn’t snag on your yarn.
Gloves – Use gloves to protect your hands through out this process. I like to wear over the elbow gloves so I don’t have to worry about splashes.
Mask – You’ll need a mask when weighing out your alum. I use a KF-94 because that’s what I generally keep on hand. A full respirator is better, but at minimum make sure you’re wearing some kind of protection.
Safety Glasses – Ok, I generally forget to put mine on, but I do recommend using safety glasses to protect your eyes from errant splashes.
Thermometer – for monitoring your water temperature while mordanting. I like a digital one, but analog is fine too.
Metal tongs – These tongs are very useful for taking the yarn out of the steamer basket.
Large bucket – Use a bucket for soaking and cleaning the yarn. If you don’t have one already, I suggest getting this set of three one-gallon giant measuring pitchers. I find new ways to use them constantly. They really are the heroes of the textile lab.
Mordanting
The first part of the process is to mordant your yarn. This allows the dyes from the plants to form strong bonds with your fiber. Without this process, the color may not stick at all, or will only stain the yarn, forming a very weak bond.

Weigh your yarn: In order to know how much alum to use, you need to know how much your fiber weighs. I like to use grams for this, because it’s so much easier to calculate. So, using your scale, weigh the yarn and write that number down.
Prepare your yarn: One of my biggest challenges when starting to dye yarn was avoiding tangles during the dye process. To avoid this, you’ll want to put at least three figure-eight ties on your skien. These should be loose enough to allow water to flow through, but tight enough to keep the yarn in order. I find that the ties they put on the Knomad hanks I buy are just right. However, I alway add one additional cotton tie in a bright white. This makes it easy to see in the pot while dyeing so I use it for handling my yarn during the dyeing process.
Soak your yarn: Fill a large bucket (or your large pot if you don’t have one) with water and add in your yarn. Push down gently on any bits that aren’t submerged and add more water if you have to. You’ll want to let this soak for at least 15 minutes. If you have longer you can leave it for up to a few hours. When removing the yarn from the bucket, I hold it by the cotton tie I put on earlier and dip it up and down a few times before gently wringing it out. This helps the yarn detangle. Discard the water.
Calculate the amount of alum needed and weigh it out: I used alum at 12% WOF. This means for every 100 grams of yarn I used 12 grams of alum. Before weighing out your alum, put on your mask. I keep my mask on until all containers containing powder are closed, any spills are cleaned up, and all powders have been dissolved into liquids. Use your scale to weigh this out either into a small bowl or onto a piece of paper (I often use a scrap of newsprint for this).
Dissolve alum and add to big pot of water: At this point, I like to fill my big pot with water and dissolve my alum in that. You can also dissolve the alum separately in your small bowl. The most important thing is that the alum is fully dissolved before you add the yarn.
Simmer yarn: Add the yarn to your pot then bring to a simmer for about an hour. I like to keep my pot between 190f and 200f. Move your yarn occasionally, to avoid scorching, but don’t stir. I like to use the same up and down motion that I use to detangle the yarn when taking it out of the bucket.
Remove yarn from pot: One hank at a time, remove the yarn from the pot and gently squeeze out the excess water. The yarn should still be quite damp, but not dripping.
Bundle Dyeing the Yarn
Lay the yarn on the cheese cloth: Take your cheese cloth and lay it out on a flat surface. Lay your yarn on top, covering approximately half of the piece of cheese cloth. You want to balance having your yarn as flat as possible (to allow more surface area to come in contact with the dyes) and gently twisting the skein (to distribute the dye across the skein more evenly). I twisted my hands of yarn twice, which was plenty for the look I was going for. When you’re happy, fold the second half of the cheese cloth over the yarn. The yarn should be fully covered by the cheese cloth.
Add your dyestuff: Sprinkle your dyestuff over your cheese cloth covered yarn. How exactly you do this is entirely up to you. The more you add, the more dye will be transferred onto the yarn. This is very much about trial and error, as each plant spreads and takes at different rates.
Roll up your bundle: The goal here is to roll up the yarn/cheesecloth/dyestuff into a tight bundle, pressing all the layers together. There’s really no wrong way to do this as long as all three parts stay together and in order. I rolled mine into log, then curled it into a spiral. Secure it with string in any manner that works for you.
Steam the bundles: Add an inch or two of water to the bottom of your pot and place you steamer basket on top. Place your bundles into the basket. It shouldn’t matter if they touch, but if you’re concerned for any reason, give them half an inch or so apart. Turn up the heat until the water begins to steam, then place the lid on top. Let steam for about an hour, checking and adjusting the heat as needed.
Remove from the steamer and let cool: Using your tongs, take the yarn bundles out of the steamer and set somewhere to cool. I usually let them cool overnight, which allows the dye to set even more. Just don’t let them sit longer than 24 hours as you may start to have microbe growth.
Cleaning and Finishing the Eco Printed Yarn
Carefully unroll your bundles: The goal here is to separate the yarn from the cheese cloth without getting the dyestuff all over it. The spent dyestuff should be disposed of, but if you can get most of it off your cheese cloth, that can be washed and reused in other dyeing and craft projects.
Gently wash the yarn: I add a small amount of wool wash or shampoo to a large bucket of room temperature water. I then gently swish my yarn a few times and check the color of the water. If the water is mostly clear, you’re fine to rinse. If not, let the yarn soak a bit, change the water, and try again. Your goal here is to get any excess dye and alum out of the yarn.

Note: It’s completely normal for your yarn to shift colors during washing or rising. Many natural dyes are very pH sensitive. Sometimes these changes can be reversed by treating the yarn with a solution of the opposite pH. For example, water mixed with vinegar or citric acid can cause colors to become warmer. This is also fun to play around with on purpose!
Rinse the yarn: Use plain room temperature water for one final rinse to get any soap out of the yarn.
Remove excess water: In order for the yarn to dry in a timely fashion, excess water needs to be removed. You can do this one of two ways: with a towel or a washing machine. If using a towel, roll the yarn up in the towel and press gently to force excess water from the yarn into the towel, then move on to the next step.

Lately, however, I’ve been using a trick I learned from a dyeing class from The School of SweetGeorgia, which works great when you have multiple hanks of yarn to dye at once. Just place the yarn neatly around the edges of a top loading washing machine and set it to run a spin cycle only (no rinsing or washing). When the drum starts spinning, the yarn is plastered up against the sides of the washer, so it gets wrung out without getting tangled! Once that’s complete, you can move on to the next step.
Dry the yarn: Air dry your yarn on a rack for a day or so. The yarn should be completely dry before you store it, so leave it out as long as you need to.
Using Your Eco Printed Yarn
Once the yarn is dry, it’s ready to be used or stored however you like! The yarn shouldn’t have issues with crocking or dye transfer and the texture shouldn’t have changed significantly. However, just to be safe I always swatch after dyeing.

However, it’s important to remember that natural dyes don’t always behave exactly like commercial yarns. Some colors will fade more quickly than others in light, while others may be more sensitive to washing. There also is a risk of color shifting if it’s exposed to high or low pH during cleaning. This can come from the water its self or from the detergent or other additives used for washing. I just see this as a natural part of the process and try to embrace it, but if you use a process like this on something you intend to gift or sell, defiantly include a note or care card.