Vibrant Watercolor Rainbows: The Wet-on-Wet Technique

Updated at: 15/05/2025

Watercolor painting offers a unique fluidity and luminosity, and few subjects capture this better than the vibrant spectrum of a rainbow. The wet-on-wet technique, where colors are blended directly on a dampened surface, unlocks the true potential of watercolor, allowing for breathtaking, organic transitions and a luminous depth impossible to achieve with dry-brush methods. Imagine the soft, diffused edges and the almost ethereal glow that only wet-on-wet can create – a rainbow that shimmers with life and movement, captured on paper.

This captivating technique, however, requires a delicate balance of water, pigment, and timing. But fear not, aspiring artists! This article will guide you through a step-by-step process, revealing the secrets to painting your own stunning, vibrant watercolor rainbows using the wet-on-wet technique. Prepare to be amazed by the results as you unlock the expressive potential of this beautiful medium.

Preparation and Safety Guidelines

Tools Needed
  • Watercolor paints (red, orange, yellow, green, blue, indigo, violet)
  • Watercolor paper (at least 9x12 inches)
  • Paintbrushes
  • Water cup
  • Watercolor palette
Safety Guidelines
  • Always work in a well-ventilated area. Watercolor paints, while generally non-toxic, can still release fumes that are irritating to some individuals.
  • Protect your work surface. Watercolor paints can stain, so cover your table or desk with a waterproof surface like plastic or a drop cloth.
  • Clean your brushes thoroughly after use. Watercolor pigments can dry and become difficult to remove if left to harden in the bristles.

Step-by-Step Instructions

  1. Prepare Your Palette

    • Wet your watercolor palette and add drops of water to each color to activate them.
    Prepare your paints: Wet your watercolor palette and add drops of water to each color to activate them.
    Prepare Your Palette

  2. Paint the First Arch

    • Begin with red in the middle, towards the bottom of the paper, painting a watery arch.
    Start with the inner arch: Begin with red in the middle, towards the bottom of the paper, painting a watery arch.
    Paint the First Arch

  3. Add Subsequent Arches with Wet-on-Wet

    • Continue with orange, yellow, green, blue, indigo, and violet, each arch overlapping the previous one in some places but leaving spaces in others to create blending and separation of colors.
    • Maintain a watery consistency for each color to achieve seamless blending.
    • Continue adding arches in the ROY G BIV order, using the wet-on-wet technique and overlapping to create beautiful color blends.
    Complete the rainbow: Continue adding arches in the ROY G BIV order, using the wet-on-wet technique and overlapping to create beautiful color blends.Complete the rainbow: Continue adding arches in the ROY G BIV order, using the wet-on-wet technique and overlapping to create beautiful color blends.Complete the rainbow: Continue adding arches in the ROY G BIV order, using the wet-on-wet technique and overlapping to create beautiful color blends.
    Add Subsequent Arches with Wet-on-Wet

  4. Control Blending and Overlapping

    • Plan where you want arches to touch before you begin painting. Use light touches and multiple strokes to achieve desired blending.
    Control blending: Plan where you want arches to touch before you begin painting. Use light touches and multiple strokes to achieve desired blending.
    Control Blending and Overlapping

  5. Manual Color Blending

    • After applying the arches, you can use your brush to manually blend colors for a more customized look.
    Manual blending: After applying the arches, you can use your brush to manually blend colors for a more customized look.
    Manual Color Blending

Read more: Reverse Silhouette Painting: Underwater Scene Masterclass

Tips

  • Use a large piece of paper: This prevents running out of room and allows for bigger, bolder arches.
  • Remember the order: Use ROY G BIV (Red, Orange, Yellow, Green, Blue, Indigo, Violet) to remember the rainbow colors.
  • Watery consistency is key: This is crucial for the wet-on-wet technique; ensures smooth blending.
  • Plan overlaps: Decide where arches should touch before starting to control blending.
  • Manual blending enhances results: Use your brush to blend colors after applying arches for a more artistic touch.

Common Mistakes to Avoid

1. Too much water

Reason: Using excessive water dilutes the pigment, resulting in pale, washed-out colors and uncontrolled blending.
Solution: Use less water on both the brush and the paper, and blot excess water with a clean cloth or paper towel.

2. Muddy colors

Reason: Mixing too many colors together creates a murky, undefined appearance rather than a vibrant blend.
Solution: Limit your palette to a few key colors and use them strategically, layering colors gradually to achieve desired effects.

FAQs

What kind of watercolor paper is best for the wet-on-wet technique?
Cold-pressed watercolor paper is ideal. Its slightly textured surface holds the water well, allowing for beautiful blending while preventing the colors from bleeding uncontrollably.
How do I prevent my colors from muddying when blending wet-on-wet?
Use clean water to lift and blend colors gently. Start with light washes and gradually build up intensity. Avoid over-mixing your colors on the palette before applying them to the paper.
My rainbow looks too flat; how can I add more depth and dimension?
Vary the intensity of your colors; some areas can be darker and more saturated, while others can be lighter and more translucent. Experiment with adding a darker wash beneath the rainbow to create a shadow effect, and consider adding details like clouds or rain to further enhance the composition.