Try These Tips for Correcting Common Watercolor Mistakes and Mishaps

From Oops to Ahh

Oops. You’re basically finished with your painting, but you notice some mistakes. Just remember that, despite its reputation, watercolor can be a forgiving medium. Using various methods, you can fix many of those vexing areas. Here’s how.

Black-Spot Removal

Easily the most noticeable and annoying error is the dreaded black spot, caused by some mysterious pigment dropping onto the paper as you painted and then drying before you noticed it. Unless the spot is in an area where it can become a “happy bird” (to paraphrase artist Bob Ross), you’ll have to remove it. There are two choices: the wet method or the dry method.

Wet Removal

This is a risky option because whenever water is added on top of a dried color, it partially reawakens the paint. Activating watercolor (especially non-staining pigments) pulls it slightly off the surface, allowing the color to spread easily. If not done properly, adding water can quickly turn a little black blemish into a large black spot. To remove the black spot, touch it with a barely damp, size 0 brush. Wait several seconds, then lightly touch the wet area with a clean, dry paper towel. Repeat this last step several times, always with a dry, clean paper towel. Pressing a wet, dirty paper towel into a wet area will lift off color around your spot or blot darker color back into the area. With patience and care, you can usually remove most of the offending spot in this manner. If this method doesn’t work, it’s time for surgery—otherwise known as “dry removal.”

With a small, just barely damp brush and clean, dry paper towels, you can make accidental paint spots disappear.
Dry Removal

While slightly terrifying, the easiest way to remove watercolor is literally to slice or scrape it from the top layer of paper, using an X-Acto blade or utility knife. I prefer utility knives, which are available at hardware stores. Make sure the blade is sharp. Using your cutting device, scrape very lightly and, using a back-and-forth motion, take out the dark spot. You want to work gently, removing only the top part of the paper without cutting through it. I recommend scraping from several different angles to remove stubborn color stuck in the grooves of cold-pressed or rough paper. After eliminating the color, use a clean, white eraser to gently remove the debris. You should be left with a light or white spot, which brings us to the next corrective technique.

If your painting surface is dry, gentle scraping with a utility knife or X-Acto blade will remove stray paint spots. Follow up with a clean, white eraser to remove debris.

White-Spot Toning

White spots are generally easier to remove than black spots. On your palette, create a small puddle of color of similar hue and value to the area surrounding the white spot. Gently drop a little of the premixed color onto the lighter area. Build up the value slowly, letting each layer dry before applying the next, and avoid painting the already colored areas. Once your white spot is of a similar value and hue to the surrounding areas, it will be very difficult to notice.

Make a white spot disappear by applying light layers of premixed color.

Lighten Color

Did you know that you can lighten a layer of dried watercolor? The secret is masking fluid (aka drawing gum). Perhaps you’ve noticed the darkened look of masking fluid when it’s removed from a painting. That’s because masking fluid, like any liquid, will lift watercolor—and the removed watercolor darkens the mask. Accordingly, when you remove the mask, the color that was underneath will be lightened by about one value (depending on whether the pigment was staining or non-staining). Each brand of masking fluid behaves a little differently, so experiment to get the desired amount of lift. For this purpose, I prefer the Pebeo brand—a very fluid mask that pulls off a lot of pigment.

To apply the mask, use a soft, clean brush. Rinse the brush frequently and change the water often. Masking fluid will eventually ruin brushes—so don’t use expensive ones. I use Cheap Joe’s Uggly Brushes. Cover the areas you want to lighten with masking fluid. Then, once it dries, remove the mask—and you’ll have successfully lightened a layer of paint. If you want to go still lighter, repeat the process.

I applied a streak of masking fluid, let it dry and then removed it, resulting in a slightly lighter area of color.

Remove Hard Edges and Streaks

What about unwanted hard edges or a dark streak in a large wash? You can fix those too. First make sure your paper is completely flat. Then spray a mist of water from a small bottle over the area that needs repair. You don’t want a puddle—just enough water to wet the edge or streak. Also, be sure you spray at least several inches from any other area on which you may be working.

Next, using a nonabsorbent tool (I use Grafix Incredible Nib), gently touch the hard edge or dark streak. Touching wet paint activates the color, pulling it off the surface of the paper—but the Incredible Nib won’t absorb color. Instead, the agitated color will spread, creating a softer edge or lightening a dark streak. To further feather the color, continue to mist the paper, keeping it slightly damp. Once you’re happy with the edge and value, let the paint dry.

Touching a Grafix Incredible Nib to wet watercolor will spread the paint without absorbing it, thus softening hard edges or lightening a dark area.


Don’t be afraid of painting mishaps. With these techniques, you can fix errors and accidents—and save your work. Having applied them to my painting Kirkjufell and Waterfall, Iceland, I can sit back, gaze at my work and enjoy the scenery.

I had a few “oops” moments when painting Kirkjufell and Waterfall, Iceland (watercolor on paper, 15×22), but they were all fixable.