The recipe we use for homemade dishwasher detergent is extremely simple.
1/2 cup liquid Castile soap (I use Dr. Bronner’s Tea Tree Oil Liquid Soap)
1/2 cup water
1 teaspoon fresh lemon juice
3 drops tea tree oil extract (Optional – I don’t use this because it’s already in my Castile soap)
1/4 cup white vinegar
Mix the water and Castile soap in a medium-sized bowl. Stir in the lemon juice and tea tree oil extract. Add the vinegar, the mixture will slightly curdle. Whisk the ingredients until everything is evenly blended. Use a funnel to transfer the mixture to a storage bottle (I use old 1gl. vinegar containers).
You’ll want to use about 3 tablespoons of the mixture per cycle at first, then decide for yourself based on your dishwasher and load size what works for you. I let my dishwasher run one time through, then add 1/2 cup of vinegar to the dishwasher and let them rinse again. This keeps the white film from appearing on dishes after the drying cycle.
***There’s a note on the original recipe, provided by my mother-in-law around seven years ago, which may be important to you: Do not substitute conventional liquid soap for the Castile soap unless it is a “low sudsing” soap. Regular soaps will produce too many suds and overflow the dishwasher***
I typically multiply the recipe by four and make a batch which lasts around two months or more, depending on how much I’m running the dishwasher. This recipe has been in use in my house for over six years now and I’ve never thought to purchase dishwasher detergent again.
Let me know how it works for you if you try it out!