Experimental Botanical Print with Petals using Alum Mordant

Here is a first attempt at creating a Botanical Print with petals gathered from around the garden (you can find further information about this technique from our Blog post Botanical Printing – an overview). It is difficult to get a clearly defined print with petals as the colours tend to bleed into the fabric.

A length of cotton and a length of silk fabric were first soaked in a solution of Alum mordant. It is important that your fabrics are dirt and grease free as this will affect how the Alum and colour is absorbed. Diluted Synthrapol is an excellent scourer and will ensure that your materials are clean. See more about PFD (prepared for dyeing).

Preparing the Fabric with Alum

The Alum mordant from George Weil comes in crystal form and needs to be dissolved in water. Make up a solution of Alum water using 2 heaped teaspoons of Alum to 500ml of water (you can make larger amounts depending on how much fabric or paper you wish to print). It is best to dissolve the Alum in about 100ml of hot water and then thoroughly stir in the final 400ml of cold water.

Soak your fabric in the Alum mordant water for 10-15 minutes, remove and squeeze out the excess liquid.

For this experiment, the damp cotton fabric was laid out onto a sheet of plastic.

Eco Print with Petals

The petals were placed randomly across the cotton fabric before sandwiching them with the length of damp silk fabric – an experiment to create two prints on different types of fabric.

Preparing the petals for the print

Silk fabric laid over the top of the petals

A sheet of plastic was then laid over the top of the “sandwich” and the stack was carefully folded over on itself by one third from the left and a third from the right to ensure that the plastic sheet separated the fabrics. This was to prevent the colours from leaching though the undersides of the fabrics.

This is where a shortcut was taken. The usual practice is to tightly wrap the parcel around a baton made from wood, sticks or plastic. This ensures that the petals are flattened tightly against the fabric once the parcel is bound with string. Our parcel was wound into a sausage without the rigid core.

The parcel was rolled up very tightly and then twisted until it looped back on itself. It was then bound with butchers twine/string along its entire length to guarantee maximum contact of the petals to the fabric.

Botanical Print ready for steaming

The final step was to wrap the parcel in a sheet of tin foil before steaming it to extract and set the colours from the petals. Follow our instructions for Steam Fixing Acid Dyes as this will produce the desired result. This can be smelly and potentially release fumes. It is recommended to open windows and ventilate the room.

Botanical Print made from Petals

The colours of pink from Busy Lizzies, Yellow from Dahlias and Purple from Bergamot on cotton left and silk right.


The result was a little underwhelming as not all of the petals gave colour. The lovely colours that have transferred to the fabric are scattered in small blobs. Future prints will be improved with experimentation and by correcting or improving the following:

  • Steam correctly. Remember that it is the heat from the steam that creates the chemical reaction. Allowing too much steam to escape or not steaming for long enough will affect the final print.
  • Choose brightly coloured petals. If the colour is pale (as some of the yellow petals in our experiment were) they are not likely to leave much colour on the fabric!
  • Use a core to wrap the print around if you want the petal colours more precisely placed. Our technique of twisting the fabric works if you just want to extract the colours for a random design.
  • Use more petals or combine with leaves. Lay out a design or pattern if you do not want random results
  • Try dyeing the fabrics with natural dyes first as this will give a coloured background for the patterning

See our attempt at creating a Botanical Print with leaves