1 1/4 cups white vinegar
1 cup baking soda
1 cup washing soda
1 cup borax
1/4 cup liquid castile soapMix in a large, non-metal bowl. I re-used (and decorated!) my previous soap tub, which worked great. Start with the vinegar and continuously stir as you add each powder. Try to stir out and break up any clumps. Finish with the liquid soap. It will seem wet, like a thick paste, but keep stirring and it will begin to flake and crumble into a moist ‘powdered detergent’. KEEP STIRRING! If you quit too early, you’ll find a very hard mass the next time you go to use it. So use them biceps and stir it to completion. You’ll end up with a sort of soft clumpy cake-y ‘loaf’, that will easily crumble off for use.
If you use plain non-scented castile soap, you may add a few drops of your favorite essential oil.
Store in a lidded container and use about 1/4 cup per load.
From House Smart Home Improvements - Windows, Doors, Furnaces, Heat Pumps, and other Energy-Efficient Home Improvements. 604-585-2020 for Free In-Home Estimate.