I was looking for alternate ways of making laundry soap when I came across this recipe. While it uses bar soap and baking soda, it seems practical because it's easier to store those two things than the big containers of store-bought laundry detergent. I always have lots of baking soda around, and I love grabbing up three bars of soap for a buck at the dollar store.
2 gallons of very hot water
1 bar of soap, grated
2 cups of baking soda (NOT washing soda)
In a medium "craft" saucepan, melt the grated soap with just enough hot water to cover. Cook on medium-low until the soap has completely melted. Be sure to stir frequently to avoid burning. Then into a large pail that you keep for this purpose, pour 2 gallons of very hot water. Add the now-melted soap and stir well. Add the baking soda and stir well again. When slightly cooled, pour into your laundry-soap container (I kept one from when I bought laundry soap at the store).
How to Use:
Use 1/2 cup per full load of wash. Double if the load is very dirty/soiled
I use whatever bar soap I found for cheap at the dollar store. There are some that don't smell the best so I might mix half a bar of Irish Spring with half of the stinky one. And sometimes I add essential oils!