This should go without saying; it’s laundry detergent, not for eating! Be sure to label your laundry detergent and keep it out of reach of small children.
2 1/2 gallons water (9.5 liters; you can round it up to 10 or down to 9 to make it easier)
1 bar Fels-Naptha soap
8 cups (2 liters) water
1 cup (200 grams) Borax
1 cup (270 grams) washing soda
Optional scent:
30 drops tangerine essential oil
25 drops rosemary essential oil
20 drops lavender essential oil (other nice scents include lemongrass, geranium, grapefruit, and tea tree for its antibacterial qualities)
Supplies:
5-gallon (18 liter) bucket with lid
Re-purposed laundry detergent containers or jars with lids
Grater or knife
Large (6 quart) pot
Large metal spoon or whisk
Stick blender, optional
Funnel
1. Measure 2 ½ gallons (9.5 liters) of water into a clean bucket and keep safely covered to protect small children and pets.
2. Grate Fels-Naptha bar or chop into small bits.
3. Meanwhile, bring the 8 cups (2 liters) of water to a boil in a large pot. Add the grated soap and stir with a metal spoon or whisk until melted. Add Borax and washing soda and stir until dissolved. Mixture will turn foamy.
4. Pour melted soap mixture into the bucket of water. Measure essential oils, if using, into the mixture and stir to combine. It will thicken slightly as you stir.
5. Cover securely and set aside to cure overnight. The mixture will congeal to form a thick gel. Whisk thoroughly (I like to use my stick blender) all the way down to the bottom of the bucket to make a smooth, pourable liquid.
6. Use a funnel to ladle your homemade liquid laundry detergent into old jugs (clean) or jars for storage. Fill containers about two-thirds to three-fourths full to allow airspace at the top for shaking. Keep one by your washing machine and store the rest.
7. Use ¼ – ½ cup (60-120 ml) per load of laundry, depending on load size and dirty the clothes are. Since homemade laundry detergent doesn’t contain stabilizers it can and will separate. Simply shake or re-blend to recombine.