Ok since I am new to permaculture and have been in the garden, i now want to try my hand at reducing chemicals inside. I still use washing up liquid (the main ones from the supermarkets) and i find the eco friendly ones a little pricey.
Old fashioned lye soap made with real wood ash lye is probably as eco-friendly as you can get. There are two types of "lye", NaOH and KOH. The sodium kind of lye is not good for plants and leads to salt buildup in the soil; the potassium kind of lye is a necessary plant nutrient. The other part of the soap molecule is a fatty acid, and it breaks down easily in nature since all organisms from bacteria to higher mammals use fats for energy storage.
If anyone has any questions about particular molecules used for cleaning purposes, throw them over the plate and I will take a swing at them.
Non-commercial dishwashing stuff is a bit of a 'last frontier' for me, but I do have a soap-shaker which to be honest, doesn't get much use (yet)
Many women from my Nana's generation used them: all the last bits of Sunlight soap (NZ made tallow-based) would go in the shaker and it would get swished around under the hot tap.
When I looked online, a got a bit of a feeling the soap shaker might be a bit of a NZ thing though.
A common wildflower, soapwort (Saponaria officinalis) has been used for centuries as a soap for delicate skin and fabrics, and also as a shampoo. A handful of leaves boiled for 30 minutes in a pint of water will produce this fine detergent.
The roots, if harvested during flower bloom contain up to 20% saponin (the active cleaning agent) as compared to only 15% for soap nuts.