Dye Project: French Broom

Back again with another dye project, using dye sources from our residential lot here in Oakland, California. This year we're going "back to the land" to discover what resources are available to us from our own place. Last time we dyed with Tulip Tree flower petals, which produced a lovely lemony-yellow dye (see Dye Project: Tulip Tree).

Today I'm dyeing with French Broom (Genista monspessulana). French Broom is a woody shrub that is native to the Mediterranean region. Broom is a nitrogen fixer that does well in poor soil, and is a prolific seed producer.

  

 

The flowers are an intense yellow, and quite beautiful, but French Broom is highly invasive in the United States. The shrub can quickly overrun native vegetation, providing little benefit for the local wildlife. 

French Broom (Genista monspessulana)
Kohler - public domain

My research on this species of Broom indicates that leaves yield a green dye, but I found little about the flowers, or a combination of leaves and flowers. Other research indicates that Scotch broom yields pale yellow or beige, but Dyer’s broom yields brilliant yellows and yellow greens. We have a self-seeded French Broom bush at the edge of our property. I have started to eradicate it, but decided to experiment dyeing with the flowers that I removed.

Self-seeded French Broom

For this project I used basic dye equipment, and a well-ventilated workspace. I used a soaking pot, a dye pot, a heat source, and a candy thermometer to keep the dye bath at a consistent temperature. I also used a strainer and cheese cloth to remove the petals and leaves from the dye bath.

Outdoor studio and basic equipment

Prepared fabric

The Weight of Fabric was about 11 ounces (312 grams), which includes:

• 2 dish towels - 154 g (4.9 ounces) 
• 2 napkins - 50 g (1.76 ounces)
• 2 large handkerchiefs - 35 g (1.2 ounces)
• 2 small handkerchiefs - 20 g (.7 ounces)
• 1 dish cloth - 57 g (2 ounces)

French Broom blossoms and stems

The fabric was scoured and mordanted. I used a gallnut mordant, followed by a bath of 20% WOF alum and 8% soda ash as a brightener. This differs from our usual values of 15% alum and 2% soda ash. I collected about 12 ounces of French Broom flowers and leaves, so, the WOF% for 11 ounces of fabric was about 109%. I gathered the flowers, and froze them to preserve the color until I was ready to dye.

Frozen blossoms help preserve color

The supplies for dyeing include:

• 12 ounces French Broom flowers
• 1/2 lemon (juice and rind)
• A gallon of water (plus more as needed)
• 11 ounces prepared cotton fabric 

NOTE: For safety, use a face mask and rubber gloves.

Extract Dye

First, extract the dye, using our basic process:

1. Add petals and lemon to the pot.
2. Simmer for an hour.
3. Soak petals.
4. Strain them.

Rinse the petals to remove dust and insects, and then add the petals to a gallon of water in a stainless-steel pot. Stir in the juice of 1/2 lemon and its rind. Bring the temperature to 160 degrees, and simmer for an hour. Note that my equipment isn’t that controllable, so I typically cook between 180 - 200 degrees. Your color results may differ if you are able to maintain a lower temperature. 

Stir lemon juice and rind into petals

Soak for three days

Soak petals and lemon rind for three days to extract all the color possible. Strain petals out of the dye bath using cheesecloth. Return the dye bath to the stainless-steel pot. The resulting liquor is pale yellow or amber, depending on the light, and has a noxious smell. A face mask and rubber gloves are recommended. I tested the pH to learn more. It registers at 3, which is quite acidic (and may be from the lemon).

Strain the petals out of the dye bath

Pale yellow or amber dye bath

Dye Fabric

Dye the fabric using our basic process:

1. Add wet fabric to dye bath.
2. Heat the dye bath and simmer for an hour.
3. Soak fabric in the dye bath.
4. Rinse and hang to dry.

Add wet, prepared fabric to the stainless steel pot, and simmer for an hour, keeping the temperature between 180 - 200 degrees. Stir periodically to make sure dye is distributed as evenly as possible. If necessary, add more water to cover the fabric. The color from this French Broom species is not very strong or dramatic. Let soak for an hour or overnight. In pursuit of saturated color, I let it soak for three days.

Simmer fabric in the dye bath

Rinse fabric in cool water

Squeeze out excess dye from the fabric. Rinse the fabric in cool water until the water runs clear. Run the fabric through the washing machine’s rinse and spin cycles, using cold water. Let the towels air dry. Two weeks later, wash the towels in pH neutral soap, like Synthrapol, and hang to dry. The resulting color is a very pale yellow. 

Hang fabric to air dry

Very pale yellow dye results (with some imagination)

The results are a little disappointing, but maybe it is for the best. I have no incentive to retain the French Broom plant, and can eradicate it without hesitation!

Learn More:

• A Lesson About Dye Plants: Broom. Blog article by Catharine Ellis.  (https://blog.ellistextiles.com/2015/05/14/a-lesson-about-dye-plants-broom/)

• Botanical Colors – Dye Flower Instructions: Creating and Using a Dyebath. (https://botanicalcolors.com/dye-flower-instructions/#:~:text=Start%20heating%20the%20flowers%2C%20bringing,don't%20let%20it%20boil).

• Weed Control Handbook, French Broom Weed Report, by L.A.S. Johnson. (https://wric.ucdavis.edu/information/natural%20areas/wr_G/Genista.pdf).