If you have ever wondered why some tie dye tutorials tell you to soak your shirt in soda ash and others tell you to just sprinkle it on, you are not alone. Or maybe you have a jug of premixed soda ash sitting in your garage and you are not sure if it is still good.
I am answering all of that in this guide. By the end, you will know whether you actually need soda ash for tie dye, how to mix it, how long to soak your project, and whether you can reuse that soda ash bath instead of dumping it down the drain every time.
Do You Need Soda Ash for Tie Dye?
Short answer, yes, if you are using fiber reactive dyes like Procion dyes (the kind I use, mostly from Dharma). Soda ash, also known as sodium carbonate, is a mild alkali that raises the pH of your fabric. That alkaline environment is what allows the dye molecules to actually bond permanently with cotton, rayon, and other natural fibers.
Without soda ash, the dye just sits on top of the fabric instead of bonding with it. You will still get some color, but it will not be as rich or true, and it will fade much faster after just a few washes. So if you want vibrant, long lasting color, soda ash is not optional.
Soda Ash vs No Soda Ash Tie Dye
The difference is pretty dramatic. A shirt dyed without soda ash starts out looking okay, but the color washes out fast and looks dull compared to a soda ash treated project. If you are going to put in the time to tie dye something, soda ash is the step that makes sure that time was worth it.
The Three Methods of Applying Soda Ash
There are three common ways to get soda ash onto your project.
- Soda ash soak. Mix a solution (one cup of soda ash per gallon of water) and soak your fabric before dyeing.
- Sprinkle method. Sprinkle soda ash directly onto your fabric before or after applying dye.
- Pariah method. Mostly used in ice dyeing, this is when you pour a soda ash solution over your project after your ice has melted. I will be honest, I have not done this method myself so I will not walk you through it here, mostly because it takes a large amount of soda ash to do it right.
How to Make Soda Ash for Tie Dye
Making your own soda ash solution is simple.
What you need:
- 1 gallon of warm water (as hot as your tap will get it, this just helps it dissolve faster)
- 1 cup of soda ash
Soda ash for tie dye instructions:
- Pour your warm water into a container.
- Add your soda ash.
- Stir until fully dissolved. A wooden spoon works great for this, just do not use it for cooking again afterward.
- The solution will look milky white at first and may have small chunks. Keep stirring until it dissolves. It will get more clear as it sits.
You can buy soda ash in 1 pound, 5 pound, or 20 pound bags depending on how much you tie dye. I personally go through it fast enough that I buy it in bulk. You can even buy a 5 gallon bucket from a pool supply store.
How Long to Soak in Soda Ash for Tie Dye
I ran a full experiment on this because I wanted real answers instead of guessing. I tested no soda ash, no soak (just dipped and squeezed), a 20 minute soak, and a 4 hour soak, then repeated the whole test a second time to double check my results.
Here is what I found. My usual 20 minute soak turned out about how I expected, nice and vibrant. The 4 hour soak actually looked more subdued right after dyeing, which surprised me. But once everything was fully rinsed and washed, the longer soak did produce a bolder, richer color overall compared to the no soak and no soda ash versions.
The moral of the story? Do not judge your project until it is fully dry and washed. There is a saying in the tie dye community, don’t cry till it’s dry, and that applies just as much to soda ash testing as it does to your finished project.
If you are short on time, a 20 minute soak gets you great results. If you want the deepest color possible and you can spare the time, a longer soak can help.
Soda Ash Sprinkle vs Soak
I also compared the sprinkle method directly against a 4 hour soak using the same amount of dye and ice on identical pieces of fabric. The soak method gave slightly darker purples, but the sprinkle method actually produced more color saturation overall, especially in the blues.
So which one is better? Honestly, it depends on what you are going for. If you do not want to keep a bucket of soda ash solution around, sprinkling is a completely valid option and still gives you a beautiful, vibrant result.
Can You Reuse Soda Ash?
Yes, absolutely, and I do it all the time. I reuse my soda ash bath until it starts looking pretty gross, then I dump it and mix a fresh batch. It probably could still be used past that point, but at a certain point it is just easier to start over.
Where to Buy Soda Ash for Tie Dye
You have a few solid options here.
- Any dye supply store (I get mine from Dharma Trading Co.)
- Amazon, usually sold in 1 pound or 5 pound bags.
- Walmart or your local grocery store. (Look for ‘washing soda’)
- Your local pool supply store, since soda ash is also used to raise pH in pools.
Fun fact, soda ash is just sodium carbonate, so any product labeled that way will work.
What to Use Instead of Soda Ash for Tie Dye
If you are in a pinch, here are the most common substitution questions I get.
Can you freeze soda ash? Technically yes, but there is really no point. Soda ash is a dry powder that does not spoil, so freezing it does not extend its life or do anything helpful. It is just an extra step you do not need.
Does baking soda work instead of soda ash? No. This is the question I get asked the most, and the answer is always no. Baking soda is a completely different compound and is not strong enough to raise the pH high enough for the dye to bond to the fabric. Do not substitute it.
Does washing soda work instead of soda ash? Yes. Washing soda, which you can find at Walmart or your local pharmacy near the laundry detergent, is actually the same thing as soda ash. This is a great option if you cannot easily find soda ash labeled as such.
Frequently Asked Questions
Do you need soda ash for tie dye? Yes, if you are using fiber reactive dyes like Procion dyes. Soda ash raises the pH of your fabric so the dye can bond permanently instead of just sitting on top and washing out.
How long should you soak fabric in soda ash for tie dye? A 20 minute soak is a great standard that produces vibrant, long lasting color. Longer soaks, like 4 hours, can deepen the color even more, but require patience since the fabric may look more subdued right after dyeing before it is washed.
Can you reuse soda ash for tie dye? Yes. You can reuse your soda ash bath multiple times until it starts to look visibly dirty or gross, at which point it is time to mix a fresh batch.
What can I use instead of soda ash for tie dye? Washing soda is the same compound as soda ash and works as a direct substitute. Baking soda does not work and should not be used as a replacement.
Want to see the full soak time experiment in action, including the sprinkle vs soak side by side comparison?
And if you want a free guide to help you get started with your next project, grab my 12 Tie Dye Folds ebook, it is completely free and walks you through some of my favorite folding techniques step by step.
Ready to shop for supplies? Check out my Etsy shop or my Amazon storefront for everything you need to get started. And do not forget, you can save 20% on Jacquard products with code ANNA at checkout.
