How Long Should You Soak Watercolor Paper?

There’s nothing quite as relaxing as sitting down with watercolor after a long day and letting your imagination run free. However, creating a beautiful piece that represents your innermost thoughts only to find it warped and buckled can be very disappointing. This is precisely why it is suggested to soak or stretch your watercolor paper before use. 

You should soak watercolor paper for 4 to 5 minutes if it weighs around 190gsm or less. If you use watercolor paper weighing 300gsm or more, you will need to soak it for 10-30 minutes, depending on its weight.

Continue reading this article for more information on watercolor paper preparation and tips.

How Long Should You Soak Watercolor Paper? Watercolor Paper Weights and How Long You Should Soak Each

There’s a clear correlation between watercolor paper weight and soaking time: the heavier the paper, the longer you need to soak it. Typically, watercolor paper weights range from 190gms to 638gsm.

Here’s a rough estimate of how long you should stretch each weight category:

• 190 gsm: about 5 minutes
• 300 gsm to 356 gsm: 10 to 25 minutes.
• 638 gsm: 25 minutes to 30 minutes.

Since the above stretching times are rough estimates, you may be better off focusing more on the paper texture than the time. A properly soaked watercolor paper should have a texture similar to that of a wet cloth.

So if you’re soaking, say, 190gsm paper and the texture change comes before 5 minutes are up, that should be your cue that the paper is done soaking. Soaking it any longer will compromise its sizing. 

Why Should You Stretch Your Watercolor Paper?

Most artists will stretch or soak their watercolor paper before use to avoid buckling, cockling, or bowing. Buckling, cockling, and bowing are all words used to refer to the texture that watercolor paper takes on when used without the proper preparation.  

When watercolor paper lighter than 190gsm is used without being “stretched,” the paper expands when wet, creating divots and hills. These cause the media to pool in the valleys of the paper. This pooling makes it harder for the artist to apply multiple washes of color or be precise with color placement. 

The same can happen to heavier paper at around 140lb/300gsm if multiple heavy washes of wet media are being applied. If the wet media is applied without issue, the paper will most likely be warped upon drying. 

How To Stretch Watercolor Paper

There are mainly two primary methods that are most popular for stretching watercolor paper. The two vary on when you would like to use the paper. Method 1 highlights how to soak the paper for later use, and Method 2 outlines how to soak it for immediate use. 

Method 1: Later Use

This method is for stretching paper to be used later. 

Supplies

• Watercolor paper
• Tray (larger in dimensions than the watercolor paper)
• Spray bottle (alternate for tray) 
• Sponge or paper towel 
• Gumstrip sealing tape
• Clean water 
• Flat sturdy board (larger than chosen paper)

Steps

1. Fill the tray with clean water and submerge your watercolor sheet. If your tray is not large enough, alternate dipping each side of the sheet until soaked. Hold the sheet and spray both sides thoroughly if you use a spray bottle. 
2. Remove the soaked watercolor paper onto the flat, sturdy board. 
3. Blot the excess water away from the sheet using a paper towel or sponge. 
4. Seal the paper onto the board using the gum strip sealing tape on all four sides.
5. Allow the paper to dry flat on the board overnight. 
6. Remove the sheet off the board using an Exacto knife, or rewet the tape and peel away carefully. 

Method 2: Immediate Use

If you plan on using your watercolor paper right away, here’s how to stretch and prepare it. 

Supplies 

• Watercolor paper
• Paper towel 
• Clean water
• Large brush
• Flat sturdy board (larger than chosen paper) 

Steps 

1. Place the watercolor paper on top of the flat board. 
2. Using clean water on the large brush, liberally wet the front side of the paper. 
3. Repeat step 2 on the back side of the paper. 
4. Soak up excess water using paper towels. 
5. Start painting on damp watercolor paper. 

Tips for Watercolor Paper Preparation

Preparing watercolor paper may be easy; however, there are things that you should be mindful of. Let’s go through them one by one. 

• Do not touch the painting area of the watercolor paper while soaking. Doing so will leave finger oil stains on the soaked paper once dry. 
• Do not use other types of tapes, such as masking or scotch, instead of gum strips. They won’t properly hold the soaked paper and will lead to buckling. 
• Do not wet gum strip tape with a sponge before wetting the paper. This will leave tape residue on the surface of your paper. 
• Leave the board horizontal when drying to avoid inconsistent drying speeds and textures. 
• Do not soak the paper for too long, as it will cause the paper to roughen. 
• Do not apply too much water to activate gum strip tape; otherwise, the adhesive will leave stains on the paper. 
• Do not use a hair dryer to quicken the process. It will cause uneven drying and lead to buckling.

Do I Have To Stretch My Watercolor Paper?

You do not have to stretch your watercolor paper. If you want to avoid buckling without soaking or stretching the paper, go for a good quality, heavy grammage paper. Paper weighing above 300gsm will not buckle or bow with moderate wet media usage.

However, art is subjective to the artist. If you want to allow the paper to take its natural form for artistic reasons, that is up to your creative process. Many artists allow the paper to buckle naturally to add dimension and texture to their pieces. 

I Forgot To Stretch My Watercolor Paper. Now What?

It’s common for beginners and experts to forget to prepare watercolor paper beforehand. If you have created a masterpiece and are sad to see it buckled and wrinkled, follow the steps below to flatten out the piece. 

Supplies

• Watercolor painting
• Spray bottle
• Clean water
• Two clean sheets of paper
• Flat board 
• Heavy items (example: books) 

Steps 

1. Use the spray bottle to dampen the back of the watercolor painting with clean water. 
2. Place the damp painting between the two clean sheets of paper. 
3. Place the sandwiched painting onto a flat surface.
4. Place the flat board on top of the painting. 
5. Add the heavy books or other weights on top of the board. 
6. Allow the painting to dry under the weights for at least 6 hours. 

Final Words

Although some artists enjoy the natural cockling of watercolor paper upon usage, others dread it. To avoid cockling of watercolor paper, soak and stretch the paper prior to use with one of the two methods mentioned in the article.

If you want to avoid the extra step of stretching your paper, purchase higher quality, heavy (>300gsm) watercolor paper. And if you do happen to come across buckling, follow the mentioned steps in order to re-flatten the painting.