Mix hot water and washing soda until dissolved. Add in castile soap and lavender essential oil and allow to sit overnight to thicken (it should become very thick). Store in an easy to squeeze bottle or a mason jar.
Notes
To use: Shake liquid dishwasher detergent before each use. Add 1-1.5 Tbs of detergent to dishwasher in proper compartment. For super sparkly dishes add vinegar as a rinse agent. As stated before, everyone has different water so if your dishes are coming out cloudy, add a squirt of natural dish soap to the dishwasher detergent in the dishwasher detergent compartment.