Natural Dyeing Basics

What is a dye?

A dye is a colored substance that chemically bonds to the substrate to which it is being applied. Dyes change the color of fiber in a way that resists fading from washing, rubbing, and light.

Some examples of natural dyes include:

• Madder
• Walnut
• Nettle
• Goldenrod
• Cochineal
• Logwood
• Indigo

While these dyes have all be used for thousands of years to create colorful textiles, which specific dyes were used varies depending on time and place. Some cultures developed specific practices with certain dyes that create even more variety in what kind of dyes and colors can be found throughout history.

Dye Vocabulary Basics

• Cellulose fiber- fibers from plant sources such as cotton, linen, and hemp.
• Protein fibers- fibers from animal sources such as wool, hair, and silk.
• WOF- weight of fiber. Literally just the dry weight of the fiber or textile you intend to dye.
• Scouring- the process of cleaning the fiber before dyeing it in order to get deeper and more even color from dye.
• Mordant- a binding agent that improves how dye binds with fiber.

Fiber Preparation

Different types of fiber take on dye differently. Natural fibers are preferable because synthetics may bind with natural dye compounds minimally to not at all. Cellulose fibers (linen, cotton, hemp) take most dyes less readily than protein (animal based) fibers. In most dye techniques, a well scoured wool will give the most depth of color.

Before dyeing, every fiber type should be well washed with a detergent that will degrease it. Soaking the fiber is also recommended, preferably overnight or longer. This will help the dye permeate the fiber. Plant based fibers don’t require quite as much care in handling as animal based fibers do. Wool, in particular, may felt during the scouring (or dyeing) process if not handled with caution.

Mordants

A mordant is a binding agent that can improve how much dye the fiber takes on from the dye bath, change the final color, and improve the lightfastness and wash fastness of the dye. Fiber will almost always benefit from a mordant, but cellulose fibers may need one to get any notable results with some dyes.

Most mordants are metallic salts, but there are others, such as tannic acid. In contemporary dyeing, many mordants are created or extracted through processes that create very specific chemical compounds that can be weighed and used with consistent results. Historically, this process was very different and more variable.

Basic Instructions for Mordanting with Alum

Measure out 15% WOF alum (potassium aluminum sulfate). To figure out this amount, weigh the (dry) fiber to be dyed and multiple that weight by 0.15. This should be the weight of your alum. Use a nonreactive, heat safe pot to mordant your fiber in. Dissolve alum in hot water, starting with a small amount of water and adding more only if needed. Once dissolved, add cool water to fully cover your fiber. After adding the cool water, add your already scoured fiber while it is still wet. Adding the fiber to a cool mordant bath and then heating slowly is particularly important for protein fibers, especially wool.

Heat the mordant bath slowly, bringing the temperature up to around 190F over at least 30 minutes. The temperature should stay below simmering. Move the fiber around gently in the water for an hour at this temperature. If mordanting wool, take extra care not to agitate or stir aggressively since this can cause felting. At the end of this hour, remove from heat and allow bath to return to room temperature. The cooling process should take a few hours at the least. Overnight works well.

After mordant bath has cooled to room temperature, remove fiber and rinse it in cool water. Hang this fiber to dry. It can be dyed immediately while still damp, but no longer dripping wet. Alternatively, this mordanted fiber can be allowed to dry completely, then stored for later use.

Variables

While many factors can effect your final outcome with natural dyes, time, fiber to dyestuff ratio, pH, and temperature have the biggest impact. These are all factors you may want to keep notes about alongside a record of the results. Each of these variables can be adjusted to get different results.

Natural Dyes for Beginners

Some natural dyes are more complicated to use than others. Indigo, as well as other dyes that contain the same dye compound such as woad, require a multistep process to change the dye compound so it can attach to fiber. Some dyes are also highly temperature sensitive and will change or stop transfering dye altogether at higher temperature, such as madder. Some, like certain lichens that can produce purple dyes, require lengthy processes to extract the dyes under very specific conditions.

Don’t let this discourage you though! There are natural dyes that are simple and effective. Some may even be easy to access. Marigold flowers, dyer’s coreopsis flowers, pomegranate fruit skins, goldenrod blooms, walnut husks, and onion skins all make great dyes.

• Measure out enough dye stuff (marigold flowers, dyer’s coreopsis flowers, pomegranate fruit skins, fresh goldenrod blooms, walnut husks, or onion skins) to equal 50% WOF.
• (Optional) Place dye stuff in a nylon lingerie bag so it doesn’t float freely in the dye bath with your fiber.
• Add to a non-reactive pot and top with enough water to easily cover the fiber when it is added.
• Add wet fiber that has been scoured already. It can also have already been mordanted if desired.
• Bring the dye bath slowly up to a point where it is steaming, but not simmering. Try to keep it between 160F-180F.
• Hold this temperature for an hour, gently moving the fiber around the dye bath to make sure all of the fiber gets more even coverage.
• Remove from heat at the end of the hour. Allow the bath to cool slowly with the fiber in it. When it is near room temperature, you may lift the fiber out, or leave it overnight before removing it from the bath.
• After removing your fiber from the dye bath, squeeze out excess dye back into the bath (you can reuse the dye bath for a second round of dyeing that will produce lighter colors).
• Rinse fiber in cool water and hang to dry. It is normal for the color to lighten a bit as it dries.

Happy dyeing!