The Cozy Painter's Guide to Acrylic Mediums
Meet acrylic painting mediums—like gesso, retarder, and flow medium—explaining what they do, when to use them, and how they make painting easier.
Acrylic paints are wonderfully versatile, and with a few simple "helpers" called mediums, you can make them do almost anything you want.
Quick Reference: Mediums for Paint-by-Numbers
| Medium | What It Does | Why It Helps |
|---|---|---|
| Gesso | Prepares canvas surface | Keeps paint from soaking in |
| Retarder | Slows drying time | More time to blend or fix edges |
| Flow Medium | Makes paint spread evenly | Easier to cover tiny areas |
| Gloss Medium | Adds shine, brightens colors | Makes finished piece more vibrant |
| Matte Medium | Soft, non-shiny finish | Reduces glare when framed |
| Varnish | Seals and protects painting | Keeps colors fresh and safe |
The Most Common Mediums
1. Gesso – The Undercoat
A primer that prepares your surface. It gives your paint something to hold onto and prevents it from soaking into the surface.
2. Retarder – The Timekeeper
Slows down the drying time of acrylic paint. Perfect when you need extra time to blend colors smoothly.
3. Flow Improver – The Smoother
Makes paint spread more evenly without watering it down. Perfect for fine details and thin lines.
4. Varnish – The Protector
A final clear coat that seals and protects your painting from dust, dirt, and fading.
Do You Need All of These?
Not at all! Start with the basics:
- Gesso (if your canvas isn't pre-primed)
- Flow medium (for smooth details)
Everything else is optional. Think of them as upgrades you can try when you're curious.
Ready to Start Painting?
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