Does Watercolor Paint Expire? How to Fix It

You head to your art cabinet with plans for a relaxing afternoon of painting. You grab your brushes and paper, but hesitate when you reach for the watercolor paints. How old are these anyways? Should you be worried about your watercolor paints being expired?

Watercolor does not expire, but it can lose quality overtime, especially if stored poorly. Overtime, the pigment in the watercolor paint will separate from its binding agent to the point where it can’t be rehydrated again. Watercolor in a palette can last longer if properly taken care of.

If you’ve spent the money on a nice set of watercolor paints, you don’t want to throw them in the trash just because they’re old. Let’s talk about how to bring old watercolors back to life and why they go bad in the first place. With a little TLC, your old watercolors could have a fresh new life (source).

How to Rehydrate Watercolor Tubes

You grab a watercolor tube and it’s hard as a rock. It seems like a lost cause. I mean, you can’t even squeeze the paint out of the tube. But, if we get creative and a little messy, we can make it work. 

Grab an X-Acto knife and very carefully cut open your watercolor tube. You’ll want to cut the head off of it and then cut down the length of it so that you can peel back the sides and directly access the paint with your brush. From there, you can either paint straight from the tube or transfer chunks of your paint to your palette. Start adding water until you get your watercolor paints to the consistency you’re looking for.

Another option is to add glycerin and/or gum arabic to your watercolor paint once you’ve cut it open. Gum arabic is the binding agent that is often used in watercolors to keep the pigments together.

Glycerin is considered a plasticizer, which helps soften the gum arabic (source). We’ll talk about how these work a little later. If you add gum arabic and/or glycerin to your paints, you’ll want to add water as well. 

Whether you decide to add water or one of the binding agents, make sure to add them slowly and assess as you go. You don’t want to flood your watercolor paint. If you do this, you’ll run the risk of overdoing it and making it worse than it originally was.

Unless you’re looking to paint with a glob of gum arabic, you want to be careful with how much you add. Remember that once you add an ingredient, you can’t take it out. Also, you can’t add any pigment, so if you mess up the balance of ingredients, you’re sunk.

If you’ve been slowly adding water or gum arabic and your watercolor paint isn’t getting much better, it might be a lost cause. At the point where your paint is too watery to use and is still separated, you may want to give up.

Remember that we aren’t rehydrating your watercolor paints just for the sake of rehydrating them. If your rehydrating attempts turn your watercolors into something you’d rather not use, then don’t use them. Duh, I know, but it’s easy to get lost in the fun of rehydrating without remembering the overall purpose.

When Is It Not Worth It to Save Your Watercolors?

At some point, you just want to ditch your watercolors and buy a new set. Even though it’s a waste of money, it sucks to struggle through a painting with watercolors that are working against you. That just ruins the fun of the art. 

If you have cheaper watercolor paint tubes, it will be harder to bring them back to life. If they were cheap anyways, you’ll probably be better off just buying a new set. If you have a more expensive set though, they may be more amenable to rehydration. If you’re hesitant to throw an expensive set of tubes away, try to rework them before you designate them to the trash.

You’ll also want to toss your watercolor paints if the rehydration isn’t working. If you have more water or binding agent than paint, you have a problem. Make sure to have a tester piece of watercolor paper with you so that you can see how your watercolor repair process is going.

If you keep painting on your tester sheet and frowning at the result, you won’t want to use it for your finished piece of art. Time to toss it. 

It’s really the science of how watercolors are made that determine whether they can be brought back to life or not. Now that we’ve talked about rehydration, let’s talk about how watercolors are made and why rehydration works in the first place.

What is Watercolor Paint Made Out Of?

Watercolor paints are mainly made out of pigments and a binding agent, which is usually gum arabic. Pigments are what make up the color of each tube. The problem is that pigments are powders in their natural form, so they need something that can make them work as liquid paint. That’s where the binding agent and other ingredients come in.

Gum arabic is a binding agent that does exactly that – it binds things together. Pigment is a powder, which means that it would fly all over the place if it could. Gum arabic helps the pigment in watercolor paints stay together. 

The majority of a watercolor paint tube is made out of pigment and gum arabic, but it also has a few other ingredients that make it come together. In order to keep the gum arabic soft and pliable, it needs a plasticizer, which is usually glycerin. Watercolor paint also has a bit of water in it, which makes sense when you think about it (source). 

Ongoing Maintenance of Your Watercolors

As with anything, your watercolors will fair better over time if you take care of them. The problem is that many of us don’t think about taking care of our watercolor paints.

If you’re using them on a regular basis, you’ll naturally be taking care of them and using them up before their shelf life. If you’re not, you’re probably not even thinking about them. At the end of the day, you want to consider whether your watercolor paint tubes matter enough to you that you’ll want to maintain them on a regular basis.

The answer is probably no unless you have a really expensive set of watercolors. 

That said, it’s important to talk about maintenance because maintenance is how you’ll make sure that you have watercolors that stay healthy over time. 

If you have watercolor paint tubes, squeeze them around every once in a while. This can be a great project for any bored children you have in the house. Just get the paint moving to encourage all of the ingredients to mingle.  

Another great way to preserve and maintain your watercolor paints is to keep them on a palette or pan that you take care of. Yes, this means taking care of the watercolors and taking care of the palette but, hey, if you paint often, you’ll want to take care of your palette anyways. Some theories say that watercolors can last indefinitely if kept on a well-maintained pan (source).

At the end of the day, if you pull out your watercolor tubes just to find that they’re rock hard, you may want to ditch them and buy a new set. Unless rehydrating them sounds like a fun project, or you have an expensive set of watercolors that you don’t want to toss, you’ll almost always end up with a better result with a fresh set of paints.

Let this be good inspiration to use your paints more often to make beautiful works of art. Make it your mission to use up your watercolor paint tubes before they dry up and you’ll find yourself with a full portfolio of watercolor paintings!