Watercolor paints are beloved by artists for their luminous washes of color and their blendable, flowing nature. However, the same qualities that make watercolors so appealing can also pose challenges, especially when painting on porous surfaces like wood. The tendency of watercolors to bleed and spread unpredictably is a common frustration. With proper preparation and painting techniques, it is possible to use watercolors on wood while avoiding excessive bleeding. This article will examine the factors that influence watercolor bleeding on wood and provide tips for how to prevent bleeding for successful watercolor wood art.
The Causes of Watercolor Bleeding on Wood
To understand how to prevent watercolor from bleeding on wood, it helps to first look at why bleeding occurs in the first place. There are two primary factors that lead to bleeding of watercolor paints:
- The absorbent, porous nature of wood
- The high water content and loose binder of watercolor paints
Wood surfaces, even when sealed and prepared, tend to be more porous and absorbent than surfaces like paper or canvas. When the diluted watercolor paint is applied to wood, the wood fibers soak up the excess water. This makes the paint bleed outwards into the woodgrain and fiber texture.
Watercolor paints themselves have a very high water content. The pigment particles in watercolor paints are suspended in a water-soluble gum arabic binder. The binder has less holding power than oils or acrylics. When the paint is diluted with water, as is done for watercolor washes, the binder's grip on the pigment is further weakened. This makes the watery paint prone to uncontrolled bleeding and spreading.
Factors that Influence Watercolor Bleeding
While all watercolors will bleed to some extent, there are several factors that influence the degree of bleeding that occurs when painting on wood:
Wood Type
The density and porosity of the wood surface will impact bleeding. Denser hardwoods like birch and maple provide a more sealed surface than soft, porous woods like pine or cedar. Knots and wood grain that run perpendicular to the surface also encourage more bleeding.
Sealer and Preparation
Sealing the wood prior to painting is crucial. Unsealed, raw wood will soak up pigment and water like a sponge. Multiple coats of shellac, varnish, or primer help decrease absorbency. Proper sanding also helps seal the surface. Oily woods may need alcohol washes to prevent beading.
Paint Viscosity
Highly diluted watercolor washes will bleed more than thicker mixes of paint. Using less water or adding a bit of natural gum to thicken transparent watercolors can reduce bleeding.
Painting Technique
Brushing on washes broadly or over-working an area leads to more bleeding than controlled, direct strokes. Letting layers dry thoroughly between applications also minimizes bleeding through the grains.
Best Practices for Preventing Watercolor Bleeding on Wood
With an understanding of what causes watercolors to bleed, artists can take steps to reduce bleeding when painting on wooden surfaces:
Choose Your Wood Wisely
Select a hardwood or composite wood surface when possible. Avoid softwoods like pine which absorb more water and encourage bleeding. Wood veneers can also provide a uniform surface.
Prepare the Surface
Proper preparation is key. Sand the wood to ensure an even, smooth grain. Then apply at least 2-3 thin coats of shellac, varnish or primer like gesso to seal the surface. Lightly sand between coats to remove dust or beads. Let dry fully before painting.
Pre-Wet and Stretch Paper
For watercolor paper mounted on wood, soak and stretch paper beforehand. This helps limit later warping and bleeding under washes.
Control Your Brushwork
Paint in a controlled manner, applying washes only where they are needed. Avoid over-brushing or soaking areas excessively. Let layers dry thoroughly before adding more paint.
Use Minimal Water
Mix paints less diluted whenever possible. Watery washes spread more and are harder to control. Using a damp brush rather than wet will also limit bleeding.
Apply a Fixative
Mist layers with a fixative like workable spray varnish between applications. This sets the painting and prevents excess bleeding.
Lift and Reclaim Paint
Use a paper towel or tissue to gently lift and absorb paint from areas that begin to bleed before it dries. This removes excess moisture and pigment.
Consider Unique Techniques
Salt, wax resist, masking fluid, or wax encaustic techniques allow for defined edges and less bleeding with watercolors on wood.
Step-By-Step Process for Painting Watercolors on Wood
Follow this recommended step-by-step process when working with watercolors on wooden surfaces:
- Select a hard, fine-grained wood, or coat a soft wood with 2-3 layers of sealant
- Sand the wood to create a smooth, even surface texture
- Wash and dry the wood if needed to remove oils or residue
- Stretch and pre-wet watercolor paper if using
- Lightly sketch out the composition in pencil
- Paint controlled, direct washes using minimal water
- Allow layers to fully dry between applications
- If bleeding occurs, gently lift paint away with a paper towel
- Mist with fixative between layers for added control
- Build up glazes of color gradually to deepen tones as needed
- Allow painting to dry fully before applying any final varnish or fixative
Recommended Paints for Wood
Choosing watercolors formulated for wood surfaces can help minimize bleeding. Here are some top watercolor options:
| Brand | Paint Name | Features |
|---|---|---|
| Holbein | Acryla Gouache | – Thicker formulated gouache/watercolor hybrid – Lower absorbency and bleeding |
| Daniel Smith | Extra Fine Watercolors | – Finely ground, controlled pigments – Designed for wet-on-wet techniques |
| Winsor & Newton | Artisan Watercolor | – High pigment load and gum arabic – Excellent staining and lifting |
Best Wood Surfaces for Watercolor
These wood surface options work well for minimizing watercolor bleeding and absorbency:
| Wood Type | Description |
|---|---|
| Maple | – Very fine, smooth grain – Harder surface resists absorption |
| Birch | – Dense, tight grain pattern – Takes prep and sealing well |
| Mahogany | – Straight, open grain – Seals effectively when prepped |
| MDF | – Engineered wood composite – Provides uniform, sealed surface |
| Plywood | – Multi-layered stable construction – Less prone to warping |
Troubleshooting Bleeding Issues
Even when taking precautions, some bleeding may still occur. Here are tips for troubleshooting and correcting bleeding:
- Allow paint to fully dry, then sand lightly to smooth ragged edges
- Gently lift and blot up excess paint with a paper towel before drying
- Use a dry brush to carefully re-define any lost edges
- Apply extra sealant to exceptionally porous areas and re-paint
- Scrape paint carefully from areas, let dry fully, then re-paint
- Sand down entire painting and re-seal if bleeding persists across the surface
Achieving Successful Results Painting Watercolors on Wood
While watercolors do require some special considerations when used on wood, stunning results are absolutely achievable. The natural, expressive quality of watercolors can beautifully enhance the organic textures of woodgrain. With smart surface prep, controlled painting techniques, and high quality paints, artists can end up with gorgeous, vibrant watercolor wood art free of distracting bleeds.
The most important thing is laying an effective foundation by sanding and sealing the wood prior to ever applying paint. This critical first step helps reduce absorbency. From there, simply allow adequate drying time between transparent layers and lift excess moisture whenever possible. With a little patience and forethought, watercolor artists can unlock the potential of painting on wood, without being limited by unruly bleeding.