Building a Better Boulder (AKA Preventing Painting Potatoes)

To say that I like rocks would be an understatement.  While some may have curio cabinets filled with nick-nacks, I have rocks.  Smooth rocks, rough rocks, satiny, shiny, sparkly, large rocks, small rocks, really, really small rocks, if it is a rock, I am intrigued by it.  So much so that I have taken the time to learn about geology.

But “knowing” about rocks does not necessarily translate to being able to paint a rock.  Why is it that so many times when we are trying to paint a scene that includes rocks and boulders, we end up with a scene full of potatoes? 

I think our answer lies not in geology, but in geometry.

When we think of rocks and boulders, we visualize shapes with rounded corners and edges, worn by time and weather.   Therefore, we begin our painting with rounded shapes.  And the more pastel we add, the rounder they seem to become.  Before we know it, we have potatoes instead of boulders. 

Rather than defaulting to the roundness our brain visualizes, look for edges, sides, and angles.  I will look at a boulder and ask myself “which ‘side’ faces the light?”, “which ‘side” is in shadow?”, “which ‘side’ faces me?”  I have found that if I begin with visualizing the boulder as being composed of sides, angles and edges, not only am I more cognizant of the relationships of light, shadow and form, but I also end up with a more interesting boulder in my painting. 

Building a Better Boulder (AKA Preventing Painting Potatoes) 1

Let’s begin with a jumble of boulders.

First, I select a few of the boulders that I believe will make interesting shapes.  I sketch in the rough shapes onto a piece of Uart 400 pastel paper.  As this is an exercise, I greatly simplify the scene and eliminate the background rock wall and the foliage.  As I sketch the shapes, I exaggerate the edges and angles.

Reference photo pf rocks.

Knowing that as I add layers of pastel, the boulders will have a tendency to become more rounded, I use an underpainting for the initial layer of color.  This accomplishes three goals.  It locks in the angular shapes.  It provides a layer of color before dry pastel pigment is ever applied.  And it establishes dark, textural elements that will make the boulders more interesting. 

I lightly drag dark shades of blue and grey-violet across the paper.  I place the darkest blue where I want the darkest shadows and deepest crags and cracks. 

Stage 2 of rock painting.

I then liquefy the pastel with Isopropyl alcohol to set the pastel into the paper.  When I am brushing the alcohol onto the pastel, I continue to visual the edges, sides and angles.

Stage 3 of rock painting.

Working dark to light, I add my darkest blue into the areas of deepest shadow and grey-blue into the shadow sides of the boulders.  I choose a grey-blue because the shadow sides of the boulders will be picking up reflected light from the blue sky (or what will be blue sky when I am done.)

As I apply pastel, I use the side of the pastel to reinforce the idea of edges, sides and angles.

Stage 4 of rock painting.

Next, I block in the sky with a mix of light blue and light turquoise.  Since I wanted these boulders to be more richly colored than the original reference photo, I incorporate dark red-violet and dark orange into the shadow areas. 

Notice that the marks continue to be made using the side of a pastel and utilizing broken color.  By lightly dragging layers of pastel, it allows the underneath layers to show through and provides the boulders with texture.  And absolutely NO BLENDING!  Blending leads directly down the road to painting potatoes.

Very little pastel has been added to this point.  But we can already see the boulders taking shape.

Stage 5 of rock painting.

Moving into the mid-values, I add ochre into the areas that are sunlit, but also into some of the shadow areas that will receive reflected light that is bouncing off of nearby rock. 

Stage 6 of rock painting.

As I begin adding the light values, I notice that some of the edges of the boulders have begun to soften and appear more rounded than I had intended.  It happens.  As more pastel is added, the crispness of edges can be lost.  And the more we add, the more edges we lose.

If I notice that the boulders are becoming more rounded than I desire, all is not lost.  I use a stiff bristled brush and carve into the pastel.  Because I began with a dark underpainting and dark pastel, those dark colors are still there.  I can carve through the lighter colors to rediscover those darker elements.  I can reestablish angles and edges.

Stage 7 of rock painting.

In the pursuit of building better boulders, visualize edges, sides and angles.  Establish the darks of the shadows, crags and crevices.  Begin with using the sides of the pastel to accentuate the geometric feeling of the edges, sides and angles.  And absolutely, do not blend!  Let broken color bring your boulders to life!

Finished rock painting.
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8 responses

  1. Great Post Tracey,
    Never mind better boulders! Good advice for better anything! Noting light direction carving out shapes etc. Also blending can so often lead to flat dead surfaces never found in nature only seen in photographs where so much via a single lens gets flattened. It’s difficult to trust one’s ability using textured, scumbled layering, but so satisfying when it works.
    Beautiful boulders!

    1. Jane – You are spot on correct! Photographs really have a tendency to flat out a scene, the textures, the shadows, and the depth. I am a big fan of layering pastels and letting those textures and colors dance. Thank you for your very kind words.

    1. Thank you Cherin! My website always has updated listings of workshops that I am teaching. And I also provide tutorials through Unison’s Pastel Academy. And per your email that you sent to me, it looks like I need to start working on developing a workshop specific to painting boulders and rocks. Thanks Cherin!

  2. Love this article! I’m going to apply it to my paintings of wooden tree stumps and stop blending. Thanks!

    1. Lori – I think that’s a perfect idea! Tree stumps, tree bark, fence posts, weathered barns, this approach conveys the textures beautifully. Enjoy!

  3. Hi Tracy,enjoyed this blog.l must admit l am a blender,but after watching you,and then trying out,l conclude less is more.Thankyou .

    1. Jean, you’re welcome! I tend to use blending selectively and with purpose. If I need to push something back or subdue it, I will use a bit of soft blending, a bit. But otherwise, I try to maintain the integrity of the pastel marks to let the colors dance.

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