Natural Dye Instructions for Wool and Silk

Material to be dyed should be properly washed (or scoured if starting with raw, unprocessed wool or silk) and well wetted before beginning.

Use 4% Herbal Mordant by weight of the dyeing material. For example, if 100 gm of material is to be dyed, then use 4 gm of Herbal Mordant. Mix in a cup or bowl with hot water to make a thin paste and put aside for about 15 minutes.

In a large pot, using about 20 times the amount of water (for 100 gm material, use 2 L of water) add a small amount of vinegar or acetic acid. If you have pH paper, it should be about pH 4. Heat the water to about 60 C (or very warm tap water is about right), then add the Herbal Mordant paste and stir well. Squeeze out the wetted material* and add to the mordant bath, turning continuously and heat to a simmer just below the boiling point (for silk, don't go over 80C or it can lose it's sheen). Maintain this temperature for 30 minutes and then remove from heat. Allow the water to cool back down to 60C then remove the material and allow to cool to room temperature. Rinse the material with water and it is ready for dyeing.

Dyeing follows almost the same process as mordanting except for the last step. When dyeing is completed the material is not rinsed but is allowed to dry. Rinsing is done only after drying to remove unfixed particles of the dye from the material. Mild soap can be used to wash the material. Rinse the material well and then dry again.

The amount of dye to be used depends on the shade desired. Using 5% weight of the dyeing material will give a very light shade, 30% a good medium shade and 50-80% will give a good deep shade. Shade charts can be seen at although actual colors will vary somewhat depending on the material.

60 C = 140 F
80 C = 176 F
100 gm = 4 oz
4 gm = .14 oz
2 Litres = 1/2 gallon

*If using wool fleece or non-superwash wool yarn, handle very gently and avoid any sudden temperature changes to prevent felting.
In obtaining consistent color, yarn is easier to dye than fabric. For fabric be sure there is plenty of water and room to move the fabric around, otherwise it is very easy to get mottling or uneven dyeing – although this can also be a desired effect.

Yarn should be dyed in skeins. The skein should have at least 3-4 ties to prevent tangling while in the dye bath but don't tie so tightly that the dye cannot penetrate.

Navy Blue and Forest Green are made using oxalic acid so it's not really necessary to add any vinegar to the dye bath.

If attempting to dye cellulose fibers like cotton and hemp, please note that Navy Blue and Forest Green will not work on these fibers. These fibers require Pure Indigo and the Indigo Vat method to get blue-based colors. There is also a better mordant for cellulose called Natural Mordant  (Myrobalan extract) available at

Other mordants, such as alum, iron and copper can also be used with these dyes.

Dyes can be combined in any ratio to create many new shades. Or dip the ends of a skein in different colors to create variegated yarns.

Blue Castle Fiber Arts is a small on-line fiber arts business and importer of natural dyes from India. We are located on the beautiful shores of Lake Ontario in Hamilton, Ontario, Canada.

This website focuses on our easy-to-use natural dyes and you will find plenty of information about them and how to use them. You can also visit our supplier's website here: Sam Vegetable Colours.