If you’ve ever watched a watercolor painting take on a life of its own, you’ve probably seen a backrun — also called a bloom — appear when you least expect it. These feathery textures happen when a wet area meets an even wetter one, pushing pigment outward in unpredictable ways.
While many beginners see backruns as frustrating mistakes, I’ve learned to see them differently. In fact, these little surprises are often what bring a painting to life.
What Is a Watercolor Backrun or Bloom?
In watercolor, a backrun occurs when a very wet brush touches a damp (but not fully dry) area of paper. The new water floods into the partially dried area, displacing pigment and creating a bloom-like shape — soft edges, radiating texture, and often in an unpredictable shape.
It’s a natural part of how watercolor behaves, and it’s actually a great way to have interesting texture unique to watercolor.
Why Do Backruns Happen?
Backruns are caused by a difference in moisture levels. And this usually happens:
• In larger washes, like skies or backgrounds
• When you add water later to an area that’s already starting to dry
• If you’re painting in a humid room and the drying is uneven
Learning to Love the Bloom
When I teach workshops, I see students get frustrated with backruns. They feel like they should have a smoother surface and the backruns look too much like a mess. I used to feel similarly in the beginning but over time, I’ve come to appreciate their unexpected beauty.
Blooms often bring:
• Atmosphere and softness to a sky
• A sense of movement or texture in a background
• A reminder that watercolor is a medium that loves freedom 😉
In fact, the soft backruns in this cityscape painting of mine became the perfect way to express the hazy, dreamy energy of early morning light. I didn’t plan them — but I wouldn’t change them either.
Also I didn't mind at all the blooms happened while I painted this piece of birds flying over an abstract sunsetting sky.
The Takeaway: Let Watercolor Do Its Thing
The beauty of watercolor is that it doesn’t always behave. That’s what makes it alive. It has a mind of its own, and a lot of times we can consider ourselves an "observer" and simply enjoy watching what it does.
So the next time you see a bloom forming, don’t rush to “fix” it. Try letting it be. You might just discover that the texture, softness, and surprise it brings is exactly what tyour painting needed.
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