Can I Compost Shampoo & Other Liquid Soaps?(From the Browse by type of thing, Household waste category | No comments yet - start the conversation)
No, you shouldn’t compost shampoo or other liquid soaps.
Most shop-bought shampoos & liquid soaps include assorted chemicals, as detergents, binding agents, colours and perfumes. Those synthetic chemicals can remain in the soil after the composting process – and that is unacceptable to many people. You would gain little from adding shampoo and other liquid soaps to the heap (other than a bit of moisture) so the risk of contamination isn’t worth it.
Specialist shampoos can cause other problems as well: anti-dandruff shampoos often include an fungicide, some pet shampoos include insecticides, and liquid soaps, especially dish washing liquid, often contain anti-bacterial agents – but in a compost heap, fungal spores, insects and bacteria are desirable things and we don’t want to harm them!
Given the level of dilution involved, some people are happy to use greywater (waste water) from their showers & baths on their garden, even if they contain suds from shampoo or soap – but we wouldn’t advise it for those new to composting, just in case. If you want to reuse your shower/bath water on the garden, consider going “no poo” or a natural alternative.