This is one of the most interesting tutorials I’ve shared in a long time. I can’t wait to show you how I made this walnut printing ink!
I was very kindly sent a beautiful hand carved fern stamp Jessica from Jess Nicole Stamps, and I planned to make some sort of plant-based ink. Interestingly, by the time the stamp arrived in the post, I had already started painting the walnut. The little paint pot was sitting on the kitchen windowsill waiting to be used for this project! I love when things overlap like this.
Thank you very much for the brand Jessica – I know I will love using this for years to come!
In this tutorial, I’ll show you how to make ink and how to stamp it onto fabric and paper. “Ink” is a thickened paint with a paste consistency. The method will work with any dye plant, but is particularly effective with tannin-rich dye such as walnut shells due to their high tannin content. Some other plants that contain high levels of tannin include pomegranate skins, oaks, oak galls, black tea…
The idea is adapted from my oak gall dye recipe in Plant Dye Zine, which you can order in hard copy or as a digital download. Both oak bark and walnut bark contain high levels of tannins, and if rust/iron is added, the brown paint turns a gorgeous black!
This may seem like a long recipe, but I promise, the method is very simple. I wrote this in great detail to try to answer as many questions as possible. I work in a simple and intuitive way and I will describe the main steps in my process. Feel free to adapt to your needs!
What do you need
Note: Do not use your kitchen tools – you only need separate equipment for paint.
- A handful of walnuts in their shells (the shells are the part that contains the dye)
- Paint pot – I used it Stainless steel rather my usual preference is aluminum and I’ll explain why in a moment
- Heat source
- Muslin cloth and strainer
- Bowl to strain into
- A smaller pot for making paint
- Iron Sulphate Crystals — I order mine from wildcolours.co.uk
- A spoon is reserved for ferrous sulfate
- Measuring cup – I used 1/3 cup
- Measuring spoon – I used 1/8 teaspoon
- 1/8 tsp gum tragacanth powder – can be found online, herbal sites such as Baldwins, also sold in cake decorating shops.
- Beat it
- A small container for paint
- A jam jar for storing paint in the refrigerator
Let’s get started
Pick a few handfuls of walnuts for your paint bowl. I picked them off the ground and many were half-eaten by squirrels, but that didn’t matter. This is a great way to use invulnerable, damaged ones.
For this occasion, I decided to use a stainless steel pot. If you follow my work, you may know that I often like to use aluminum, but on this occasion I decided that stainless steel would be better. I knew I’d be soaking the nut for a few days and I just didn’t want a mess in one of my aluminum pans – metal is reactive and can be very difficult to clean. Stainless steel felt like the best choice. Plus, I wasn’t worried about needing the mordant benefit of the aluminum pan, since I’d be adding iron to the paint to act as a mordant instead. Let’s not forget the tannins in the walnut, which is a natural mordant.
I chose to keep my walnuts whole because it was the simplest thing to do, but you can decide to break them into smaller pieces to expose more surface area. If you do, put them in an old pillowcase or bag and tap them with a hammer. It is better to do it outside.
Add the walnuts to your pot and cover with water so they are all submerged.
Heat the walnuts for about an hour to start removing the paint. You will notice that the water turns brown and the walnut shells darken quite quickly.
At this point, you can leave the paint container in a cool place for a few days and let the paint darken even more. The only thing to consider is that you want to prevent it from getting moldy, so try to find a fairly cool place. Keep an eye on your paint pan every day and see how dark it is and check for mold. If you see a small spot of mold, remove it and start using the paint immediately. I think I left my pot for about 4 days and it was a very rich chocolate brown. If you want, you can add a small piece of cloth to the paint and check the color every day and control the color depth of your paint. Some people soak walnuts for weeks or months during the cool winter, so there are many ways to do this.
When you are satisfied with the depth of color, strain the dye through a sieve lined with muslin cloth into a bowl. The cloth is important to hold all the small pieces.
Your paint is now ready to use for many projects. Use it as a dark brown dye or iron it black, which I’ll show you in the next section.
We only need a small amount of paint to make the print paste in this blog post, so there will be plenty of walnut paint left over for other projects. Use it to paint fabric, wooden beads or even paper – the choice is yours!
Now let’s thicken the paint and turn it into paint
I followed my oak gall dye recipe from the Plant Dye Zine.
1. Measure the paint and pour it into the smaller pot. A basic ratio for dye is 1/3 cup dye to 1/8 tsp gum tragacanth, so decide whether to use that amount or double it.
2. Sprinkle a small amount of iron sulfate crystals on the paint. For this part, I work intuitively and just watch the color change from brown to black. Stir and observe. If you think it could do with a little more darkening, add a little more ferrous sulfate. We aim for black.
3. Now put your pot of paint on very low heat and sprinkle in the gum.
4. Mix the powder. It will dissolve completely as you heat it.
5. Now there are two things you can do at this point. We are aiming for a thicker paint consistency than we currently have and need to allow the extra water to evaporate. If we add more gum to thicken it, then it will just have more of a jelly consistency, which is not what we’re looking for. We want the dye component to be more concentrated.
- I poured the mixture into several small containers and let the paint evaporate on the windowsill for a few days. I know it sounds pretty tedious, but it works pretty well. The iron will stop it from getting moldy.
- An alternative is to continue to heat the paint on low in the oven and allow more water to evaporate. Just don’t let it burn and make sure to stir constantly. It will thicken as it cools, so it can be difficult to judge how much to heat it.
I prefer to put it on the windowsill because it won’t burn and you can check it every day and use it at the perfect stage. At room temperature, you can see the texture really well and test it to see if it works well. If it thickens too much for your taste, add a drop more water.
6. When you are satisfied with the texture of your ink/paste, start using immediately or refrigerate for later. Pour into a jam jar and label clearly to refrigerate. It can be stored in the refrigerator for a long time – the iron will stop it from getting moldy. I think it’s fine to use for a few months, but obviously watch it carefully and other people in your house don’t mistake it for sauce!
Let’s start stamping!
I stamped on fabric and paper.
- The fabric was mainly cotton and a piece of bamboo viscose. All were previously dyed with vegetable dyes and were originally treated with soy (soy) milk, which acts as a binder between vegetable fibers and vegetable dyes. You can pre-iron your fabric to remove wrinkles.
- The paper was a handmade paper texture that absorbed the paint beautifully.
There are different ways to apply printing paste to your stamp.
- I chose to apply it carefully with a brush because that’s what I get easily. The downside to this is that you can lose detail in the stamp as the paste can fill the stamp too much. However, I did a few tests with it and was happy with the results, so I continued with this method.
- Another option is to pour the paste into a large flat container (you can reuse plastic food packaging) and seal the paste to take away. The downside is that you can end up with too much putty, which means you’ll lose detail in the design.
- A third option is to apply the paste to your seal using a roller. This will give you a more even coverage.
Whichever option you choose, carefully examine the rubber stamp to make sure it is evenly coated before pressing it onto the fabric. Make several test prints to get a feel for how the paint transfers to the paper or fabric.
When you press down on your stamp, be sure to apply even pressure to all sides of the stamp so that the paint transfers evenly. However, don’t get too caught up in an absolutely perfect result and try to accept variations in texture and finished result. This is a homemade pie and we stamp by hand. It will never look like it was printed digitally, and that’s not what we’re aiming for anyway. If you’re printing a repeating pattern, some faded prints will add interest to your finished piece.
I recommend applying the ink with a roller for the smoothest result.
After you finish printing, set the paper and fabric aside to dry. The paper can be used immediately after it dries, but the fabric will need another process to help the paint set.
After the ink is completely dry, we will put the paint on the fabric. I recommend ironing on the hottest setting your fabric can handle. I used a high heat on the iron for the cotton, but the bamboo viscose needed a lower setting. Cover with a tea towel or similar cloth, iron the marks several times.
At this point, you can either rinse off the excess dye from your fabric or leave it for a few days before rinsing, which can help retain more color. When washing your fabric, first rinse in plain water to remove loose dye, then gently wash with detergent. My favorite washing up liquid is Greenscents (available in the UK).
Wash the fabric in fresh water, wring it out, then dry it. You can also use a gentle setting on your washing machine if you prefer.
When dry, quickly iron the fabric and enjoy!
Here are the results after washing:
How long does the color last?
The high tannin content combined with iron will give the print very good color fastness!
Drawing on paper
The paint has a creamy texture and is nice to paint with. Look how smooth those lines are…
Additional ideas to try
For more botanical dyeing recipes and tutorials, check out my books and ebooks: