Why clean fabric is the key to brilliant eco prints and natural dyes

Scouring might not be the most exciting part of textile dyeing, but it’s absolutely one of the most important, especially when you're working with cellulous (Cotton, & linen) natural dyes, indigo, or eco leaf printing.

If you’ve ever wondered why your colours didn’t take, or your prints looked pale or patchy, it might come down to one simple thing, your fabric wasn’t properly scoured.

What Is Scouring?

Scouring is the process of deep-cleaning fabric before dyeing or printing. It removes:

• Factory finishes
• Oils and waxes from spinning or weaving
• Natural plant residues (in cellulose fibres)

Why Cellulose Fabrics Need It Most

Fabrics like cotton, linen, and hemp (cellulose fibres) are particularly waxy and tightly structured. They often come from the mill with invisible coatings that resist water—and if they resist water, they’ll also resist dye.

Scouring makes a dramatic difference to colour absorption, definition, and fastness when eco printing on linen or cotton.

Protein Fibres Are Delicate

You can scour wool and silk, but it must be done gently. Protein fibres don’t need as much processing, and aggressive scouring can damage or shrink them. A mild soak in a wool wash or pH-neutral detergent is usually enough.

What Do You Use to Scour?

For cellulose fibres, you can scour with:

• Soda ash (washing soda) – lifts oil and opens fibres – **Cotton and Linen only not Silk or Wool
• Synthrapol – textile detergents for deep cleaning
• Dish soap will work as well

Here’s a basic formula:

1. Fill a large pot or bucket with hot water.
2. Add 1 tablespoon of soda ash per litre of water. Or a few drops of dish soap.
3. Soak your fabric for 1–2 hours (or simmer very gently for 30–60 minutes).
4. Rinse thoroughly and dry.

The Results Are Worth It

Yes, it takes extra time. Yes, it’s a bit tedious. But here’s what proper scouring gives you:

• Stronger colour take-up in natural dye baths
• Clearer, sharper eco prints
• Longer-lasting colour that won’t wash out quickly
• A more even, professional finish

In natural dyeing, every step builds on the one before it—and scouring is the first, essential foundation.

Whether you're working with a eucalyptus leaf or an indigo vat, scouring helps your fabric say yes to the colour. And that makes all the difference.

Warmly,
Jacqueline Damon
Tweed Valley Textile Company