A LESSON TO DYE FOR
An Integrated Science-History-Art Unit On Plant Dyes

Diane Grau, Ordean School, Duluth, MN
Bruce Jones, The Blake School, Hopkins, MN
This unit introduces students to plant dyes and their history and highlights invesitgative skills as they explore variables in their own plant dyeing.

Science is more meaningful for most students when it is learned in some context which is relevant to something else they have learned or to real life. This unit was designed to do both by building on a science unit on plants that discusses flowers, roots, leaves, bark, seeds and other plant parts. The integration of plant science with stories from history gives a human touch. It connects the learning to previous learning of colonial or world history, for example. Anecdotes bring in drama, economics and geography as well. Students practice numerous scientific methods as they carry out controlled experiments and trial-and-error experiments. Connections with art are made as the students use the results of their dyeing experiments to make some handcrafted items, a real-life application. Because students are involved in gathering supplies and producing displays and handcrafted objects, they take ownership of their work. All materials are low cost.

Level: Grades 5-8
Time Frame: One day to endless

Table of Contents

This curriculum module was developed as part of a project sponsored by SciMath-MN and The Bakken Library and Museum. Click to see a directory of other curriculum modules using history and philosophy of science in this series.


Teaching Methods:
Evaluation:

A Note on Materials and Costs:

Materials are all low cost. Old kitchen supplies may be used: crockpots or steel pans and hotplates. Items hay be donated or found at Goodwill other places where used items are sold. Plant materials may be gathered and brought in by students.


EXPLORING COLORS FROM PLANTS

Objectives:

  1. The student will develop rudimentary skill in documenting a scientific investigation.
  2. The student will investigate a variety of plants and various parts of plants to discover the colors which can be obtained by a simple rubbing technique.

Rationale: Curiosity can be aroused with a simple awareness raising exercise which can lead to further investigation as well as an understanding of how simply scientific discoveries may begin.

Context: Introductory hands-on activity into a study of plant dyes as part of plant unit in science.

Procedure:

  1. Using paper 8 1/2" x 11" supplied in class or student's own plain paper of the same size, fold several pieces of the paper in half and assemble as a booklet.
  2. Design a cover for the booklet. Be sure to include your name and room number.
  3. Select a plant and on the first inside page of the booklet sketch the whole plant if the plant is a bush, weed, grass, or flower. (You may want to sketch it on other scratch paper first for practice.) Trace a leaf if you are using part of a tree. Pick the part of the plant you intend to use. Show respect for nature and pick only as much of a plant as you will need. Do not take bark from a live tree. Get permission before getting plants from anyone's yard other than your own.
  4. Write complete sentences telling where the plant was found...in a yard, a woods, a pond, etc. If you use parts of plants that you bought in a grocery store, tell whether the plant would be grown in very warm places, such as a rainforest, or in areas with a warm climate, such as Florida, or in areas such as northern Minnesota which have a short growing season. Use field guides to try to identify plants.
  5. Rub the part of the plant that you have chosen to use onto a piece of scratch paper to test it to determine what color it will make and how easily it spreads. Coarser paper such as construction paper works best.
  6. In your booklet write complete sentences telling which part of the plant you used and what color marks it made. If it did not make a color, you should tell that also.
  7. You need to follow steps 3-6 for each plant you use. Your booklet must have at least eight plants that you tested for color...no more than two for green unless you include more than eight plants.
  8. Now choose at least four different colors that your plants have made and use those plant parts to create a scenic picture. On an 8.5" x 11" piece of white construction paper create a picture by again using the rubbing technique with the plants. The picture could include such things as trees and other plants, animals, water, a sunrise, sunset, rainbow, etc. On the page in your booklet where you show that plant tell...in complete sentences...what part of your picture was made by using that plant. You may use soil to create some brown or black tones in your picture, but this will not count as one of the required four plant colors.
  9. You may use paper other than the paper supplied in class for your picture but a heavy, rather coarse paper works best.

EXPLORING PLANT DYES

Time: Two sessions, 30 minutes to 1 hour each

Objectives:

  1. The student will explore the dyeing qualities of different plant materials which are mixed with hot water.
  2. The student will keep written records and tangible samples of the Òdiscoveries.Ó
  3. The student will look for patterns in the observed dying, to determine which dyes might be worth further work on a larger scale.
  4. The student will use safe techniques for handling hot water and dyes.

Materials:

Teacher Reference and Preparation:

  1. This is an exploratory activity, designed to get student interest through discovery.
  2. Assign students to bring in a variety of plant materials with which to experiment during the week prior to the experiment: cedar shavings, beets, berries, marigold blossoms, turmeric, red cabbage, tea, coffee grounds, etc. They could also bring a variety of white fabrics such as old t-shirts or athletic socks.
  3. On experiment day, heat several gallons of water. A 50-cup coffee pot works well as long as it is clean.
  4. Have enough beakers or coffee mugs for each student or pair of students. Plan for how they will be carried...handle on mugs, or hot mitts if beakers, etc.
  5. Emphasize safety, and the need for wearing goggles when handling and stirring hot dyebaths. Aprons or other protective wear would be a good precaution to protect clothing from splatters.
  6. Demonstrate how to stir without spilling, and how to handle hot fabric with tweezers.
  7. Demonstrate procedures for labeling paper toweling or cloth.
  8. Establish procedures for clean-up, including storage of dyed towel or drying.
  9. Show the kind of finished sampler or booklet which will be produced.

Student Procedure:

  1. Safely use the knife to cut up a beet or other material finely, or grind tougher material between two bricks. Put it in a heat-resistant container and add hot water. Stir or mash thoroughly. Add small samples of fabric. Allow it to soak for about five minutes while you prepare a tray lined with paper toweling or cloth. Label the toweling with masking tape or by writing directly on the towel the name of the plant dye. After about five minutes the material may be removed with the stick or tweezers, and set on a tray lined with paper toweling. Allow to dry.
  2. Follow clean-up procedures you are given.
  3. Explore with dyes by repeating these methods, documenting on the towels your results. Share results and plant materials as you work.
  4. The following day when dry, the fabrics (or even paper towel) should be assembled in a booklet or small poster, documenting the results.

Follow-up:

  1. Use the results as a springboard for decision-making about dyes to use again in larger-scale dyeing projects. See projects which follow.
  2. Discuss the times we get dyes (stains) which we want, and those which we do not want. Discuss what seems to make some stains harder to remove, and how people may have learned in history what plants make good dyes.
  3. A follow-up experiment could be to try washing out the dyes, if done on fabric.
  4. Another follow-up experiment could be to add a small amount of alum and cream of tartar to the dyebath and see how this might affect color (and washability).


LARGE-SCALE EXPERIMENT ON DIFFERENT PLANT DYES

Time: One session of an hour and a half. Follow-up projects take additional time.

Objectives:

  1. The student will use safe procedures for dyeing a quantity of materials to be used in a class project.
  2. The class will conduct a controlled experiment, comparing dyes obtained from different plant materials on one particular material (cornhusks if making cornhusk dolls or decorative wreath; wool yarn if making a small weaving project; cotton floss if making a cross-stitched bookmark; eggshells if making decorative eggs). 3
  3. The student will share the results of the experiment, both verbally and materially with others in the class.
  4. The student may use the dyed material to make a cornhusk doll or wreath, small weaving project, cross-stitched bookmark or decorative eggs.

Materials:

Teacher Reference and Preparation:

  1. Decide on a class project, in which student groups will prepare different dyed materials for use by the rest of the class: cornhusks if making cornhusk dolls or decorative wreath; wool yarn if making a small weaving project; cotton floss if making a cross-stitched bookmark; eggshells if making decorative eggs. Presoak this material in water until soaked through.
  2. Students could be asked to bring in supplies (see below) beforehand.
  3. Student groups or pairs should each be responsible for one dyebath. In general, there should be about one fourth water, one fourth dyestuff, and one half material to be dyed in each dyebath. Groups may use materials such as red cabbage (purple dye), tea (brown or tan), cranberry (pink), grape juice (purple), turmeric (golden yellow) , marigold flowers (yellow), black walnut hulls (black or brown), dandelion (yellow, yellow-green, onion skins (yellow-tan), berries (various colors) and marjoram (green). The more groups, the more colors the group will get.
  4. For best results, start with cold water. Start with hot water if time is a problem.
  5. Cut up cheesecloth or nylon hose so it is ready for students to make their own sacks filled with plant material, like big tea bags.
  6. Emphasize safety, and the need for wearing goggles and protective clothing when stirring hot dyebaths.
  7. Make provisions for weighing fiber beforehand, or for students to do so. This is useful if alum and cream of tartar are being added. These additives could be skipped, but the dye may not “fix” as well..
  8. Plan on something else for students to do while the dyebath simmers for an hour. Another possibility is to get them simmering near the end of the day, and let them cool off in the pots overnight.
  9. Demonstrate careful rinsing technique before students rinse the fabric. Emphasize the protection of eyes, skin and clothing.
  10. Establish procedures for clean-up, including storage of fiber as it dries.
  11. If possible, show sample projects which can be made with the dyed fibers.

Student Procedures:

  1. Put on protective clothing and goggles. With your partner, safely use a knife if needed to cut up plant material finely. If grinding a tougher material such as sumac berries, use two bricks or mortar and pestle.
  2. Place chopped up plant material in cheesecloth or nylon hose and tie shut, and add to water. The amount of plant material is more important than the amount of water.
  3. Add about 1 tablespoon of alum and 1 teaspoon of cream of tartar for every 4 ounces of fiber.
  4. Mix, then add the fiber. If yarn or floss is to be dyed, make it into loosely tied skeins to prevent tangling.
  5. Heat the water (simmer, not boil), stirring regularly, for about an hour. This can be shortened if needed. Cover if you have lids. If water evaporates, add enough to cover the fibers.
  6. Allow the dyebath to cool.
  7. Remove the fibers with gloved hands or strainers, and rinse in water repeatedly until the rinsewater looks clear. Hang it up to dry. Be sure to label it so others will know what dye was used.
  8. Clean up carefully as directed.

Follow-up Projects:


LARGE-SCALE EXPERIMENT ON DIFFERENT FIBERS

Time: Two sessions: One session of an hour and a half. Second session of about 30- 45 minutes.

Objectives:

  1. The student will use safe procedures for dyeing a quantity of materials to be shared as part of a class experiment.
  2. The class will conduct a controlled experiment, comparing dyes obtained from different plant materials on different fabric materials (wool, cotton, silk, rayon, and other artificial and natural fibers).
  3. The student will share the results of the experiment, both verbally and materially with others in the class.
  4. The student will use some dyed material from each of the groups to make a display of the dyeing effects of different plant materials on various fabrics.

Materials:

Teacher Reference and Preparation:

  1. Decide which fabrics will be tested. Cut enough pieces of each so that each student will have a swatch of fabric or material in the end. Presoak this material in water until soaked through.
  2. Students could be asked to bring in supplies (see below) beforehand.
  3. Student groups or pairs should each be responsible for one dyebath. Each dyebath will require a pot and hotplate or a crockpot. In general, there should be about one fourth water, one fourth dyestuff, and one half material to be dyed in each dyebath. Groups may use materials such as red cabbage (purple dye), tea (brown or tan), cranberry (pink), grape juice (purple), turmeric (golden yellow) , marigold flowers (yellow), black walnut hulls (black or brown), dandelion (yellow, yellow-green, onion skins (yellow-tan), berries (various colors) and marjoram (green). The more groups, the more colors the class will get.
  4. For best results, start with cold water. Start with hot water if time is a problem.
  5. Cut up cheesecloth or nylon hose so it is ready for students to make their own sacks filled with plant material, like big tea bags.
  6. Emphasize safety, and the need for wearing goggles and protective clothing when stirring hot dyebaths.
  7. Make provisions for weighing fiber beforehand, or for students to do so. This is useful if alum and cream of tartar are being added. These additives could be skipped, but the dye may not fix as well..
  8. Plan on something else for students to do while the dyebath simmers for an hour. Another possibility is to get them simmering near the end of the day, and let them cool off in the pots overnight.
  9. Demonstrate careful rinsing technique before students rinse the fabric. Emphasize the protection of eyes, skin and clothing.
  10. Establish procedures for clean-up, including storage of fiber as it dries.

Student Procedures:

  1. Put on protective clothing and goggles. With your partner, safely use a knife if needed to cut up plant material finely. If grinding a tougher material such as sumac berries, use two bricks or mortar and pestle.
  2. Place chopped up plant material in a nylon hose and tie shut, and then add to water. The amount of plant material is more important than the amount of water.
  3. Add about 1 tablespoon of alum and 1 teaspoon of cream of tartar for every 4 ounces of fiber.
  4. Mix, then add the fabric.
  5. Heat the water (simmer, not boil), stirring regularly, for about an hour. This can be shortened if needed. Cover if you have lids. If water evaporates, add enough to cover the fabric.
  6. Allow the dyebath to cool.
  7. Remove the fabric with gloved hands or strainers, and rinse in water repeatedly until the rinsewater looks clear. Hang it up to dry, or spread the pieces out on paper toweling. Be sure to label it so others will know what dye and fabric was used.
  8. Clean up carefully.
  9. When dry, make a display of the different fabric samples, labeling with names of fiber and dyestuff. A poster or a notebook are possibilities.

INVESTIGATING CHEMICAL MORDANTS, AFTERBATHS, MIXED DYES, AND OVERDYEING

Overview: For the advanced student or class it may be interesting to investigate some additional ways of varying color, using chemicals.

Vocabulary:

MORDANTS
are metallic salts which help dyes to bind to the fibers, making the color more permanent. Mordanting can give some variations in color, especially when wool is dyed. Mordants also help brighten many colors and make them more lightfast. Many plant fibers such as cotton do not respond so much to mordanting, so it is suggested that this experimenting be done on wool.

AFTERBATHS
are chemicals added to the rinse that can make use of acid or alkaline substances to make changes in the dye color at the end of the dyeing process.

MIXED DYES
as the name suggests, are dyes made of different dyestuffs mixed in a dyepot.

OVERDYEING
is the dyeing of one dye over another to create a new or third color.

History:

For thousands of years, people in cultures around the world have been experimenting with mordants and afterbaths Early American colonists used (among other things) salt, vinegar, urine, and oak galls, which are the lumpy growths found on oak branches where insect larvae distort the normal growth. The ashes of burned juniper branches were used by Navajo women, the Ojibwa used wood ash, rusty water and clay. Metal pots themselves released meals into the dyebaths, so copper, iron and other pots would sometimes yield different colors in the dyed product. (Information adapted from
Colors from Nature by Bobbi McRae.)

Reference:

Teachers will find it helpful to read about mordants in one of the books in the bibliography, to become fully acquainted with the chemicals they are about to use. Some of the mordants are very poisonous, and all (except alum) should be used in a very well ventilated room or in the outdoors. Do not use these chemicals without good air flow, and without proper protective clothing and goggles. Many of the following activities could be a good real-life connection for students studying elementary chemistry.

Safety Tips
Work in a well-ventilated area.
Wear plastic or rubber gloves when handling mordants, afterbaths or wet, mordanted fibers.
Cover the pots while mordanting.
Clean it up spills right away.
Add chemicals to the water, not water to the chemicals, to avoid splashing or quick reactions.
Never eat or drink when working with chemicals.

Experiment with Premordanted Wool
(mordanted before dyeing)

If a teacher wishes to have students experiment on mordants but is short on time or concerned about safety, one alternative is for the teacher to premordant the wool, then have students dye it in their dyebaths, as described in Dye Experiment. A teacher could mordant material in the summer, and dry it for later use during the school year. Below are brief summaries of procedures for premordanting.

How to Mordant

  1. Make skeins of the wool, like lassos or coils. Tie loosely to prevent tangling.
  2. Soak wool in warm water with a few drops of mild dishwashing liquid.
  3. Prepare a warm water bath in a stainless steel or enamel (nonreactive) pot, with enough water to cover the wool a little later.
  4. Mix one of the following mordants with hot water in a jar, and stir it into the pot:
  5. Rinse the soap out of the wool and squeeze the water out with care. Put the wool in the mordant pot.
  6. Simmer (not boil) for one hour, keeping pot covered. Keep the wool under water, and occasionally turn the wool gently. Add water as needed.
  7. Let it cool on its own, preferably overnight. Keep it covered.
  8. Take wool from the bath and rinse. Stainers or colanders may help. Be sure to handle with gloves. Let it drain.
  9. Dye it right away, allow it to dry in a dark place, or refrigerate in plastic bag if it will be used in a couple weeks.
  10. For dyeing, see directions in Dye Experiment.

Experiments with Mordanting

Students with some chemistry background and ability to follow safety precautions may be able to do the mordanting themselves. Some ways to adapt the above activity are:

Experiments with Afterbaths

If students are dyeing sufficient quantities of fabric to do experiments on some of it, they may enjoy experimenting with afterbaths. It is important to emphasize the use of goggles and protective clothing, and care in handling the chemicals. After dyeing is completed, acid or alkaline chemicals may be added to the final rinse. This might remind students of a hair rinse.

Experiments with Mixed Dyes

The sky is the limit with combining plant materials in a dyebath. Undoubtedly this is how people learned in history how to get new colors.

Experiments with Overdyeing

New colors may be discovered by dyeing one color, then dyeing a second time with another color. In history, Saxon green was obtained by dyeing blue over a yellow dyed wool, for example. Do not assume you will get the color you expect. Overdyeing, just like any dyeing, is full of discoveries. In fact, adding yellow over blue will give a different color than blue over yellow.

Have fun experimenting!