When we wanted to create naturally dyed green fabrics for our set landscapes, we called upon artist Lena Olson for some help. While most people would first dye with indigo and then overdye with marigold, Lena’s intuition told her to try the opposite so she could better control the green hues by doing multiple indigo dips. And the results couldn’t have turned out better!

We used organic cotton sherpa and organic cotton terrycloth, but you can experiment with any natural fibers. Before beginning, you will need to weigh the fabric you would like to dye on a scale to get the WOF (weight of fiber). This number will help you calculate how much of each ingredient you need, based on either the ingredient’s instructions or our instructions below.

You will also need to scour your fabric, which essentially means to clean it. We used soda ash, or sodium carbonate at 1-2% the WOF. Botanical Colors has a great article on how to scour here.

• Organic cotton fabric
• Oak Gall
• Aluminum Acetate
• Mexican Merigold extract
• Indigo
• Calcium Hydroxide
• Fructose
• Stainless Steel Dye Pot
• Stirring utensil

1. Add scoured fabric to an oak gall tannin bath. Follow the directions on the ratio to use based on the WOF. To speed the process, heat the oak gall bath to 180 degrees and submerge the fabric for 1-2 hours or soak it overnight for darker shades and deeper penetration of the fibers.

2. Rinse gently, but do not wash out.

3. Add the fabric to a mordant bath of aluminum acetate at 10-15% WOF (weight of fiber). Weigh out your aluminum acetate and dissolve it in a bit of warm water. Fill your pot with hot water and add the dissolved aluminum acetate. Add your fabric and heat to 180 degrees for about an hour and a half, stirring every 20 minutes.

4. Dissolve Marigold extract at 5% WOF in hot water to make a paste. Add to stainless steel pot and heat to 180 degrees F. Add your fabric. For this project, Lena soaked all fibers for at least an hour and a half. When desired color is achieved, remove and rinse.

5. Create a 1-2-3 ratio indigo dye bath with indigo, calcium hydroxide (type-s building lime) and fructose dissolved in hot water separately. Then add to your container of hot (boiled) water, making sure you have enough liquid to submerge the fabric fully.

6. Take a stirring utensil and begin to stir in one direction. As you gain momentum a “vortex” will form. Stir this way for about 2-3 minutes. Be careful not to whip the solution. Avoid oxygen!

7.  Check on your container in 30 minutes. There should be a coppery sheen to the liquid and a dark blue foam on top called an indigo flower. If not, don’t worry, simply stir a little more and give it more time. Since fructose vats can mature over time, maturing for 1-2 days will have more available indigo.

8. To dye, push the indigo flower to one side, and dip your fibers. Submerge them for 5 minutes, taking care to stir them very gently for an even dye.

9. Remove and hang dry. As they hang in the air the fibers will turn blue as the indigo oxidizes.

• After the mordant bath, you can store your fabric to dye at an later date or transfer it directly to the dye bath
• For the terrycloth, Lena lessened the amount of Marigold extract to 2-3% WOF for lighter hues.
• For indigo, the WOF doesn’t really matter, what does matter is the amount of liquid you need to dye the fibers.
• Indigo vats love to be warm. For smaller vats, use a stainless steel pot that can stay on a heat source. For larger vats, start with boiling water. If you want to reuse the vat, you will have to heat it up again if it goes cold.
• For Indigo, once you choose your container you cannot pour it into another container. Do not add oxygen to your indigo vat. If you do, you need to rebalance the vat with more fructose and time. Lena would suggest ordering more fructose than you need, so that you can balance the vat as needed. Dipping large amounts of fiber can introduce oxygen to the vat.
• The metal of the pot will affect the color. An iron pot will darken shades, for example. We used a stainless steel pot. If you don’t, it’s important to note that some of your dye will bond with the pot.