The same procedure can be followed using berries, roses, and other anthocyanin containing plants. This does not work for green cabbage. The same anthocyanins are not present in green cabbage.
You can substitute ethanol for isopropyl alcohol, if necessary or desired.
It is possible to make your own litmus powder if you are a competent chemist. However, the process is quite involved and includes adding several compounds such as lime and potash to ground lichens and allowing weeks for fermentation.
You can make red litmus paper (that turns blue when exposed to a base) by adding acid to the indicator solution before soaking your paper.
