In a large mixing bowl whisk together the baking soda, cornstarch, epsom salts, and citric acid.
In a small bowl mix the jojoba, essential oils, and water together.
If using flowers set some in the bottom of one of the molds.
Add the wet ingredients to the dry ingredients a little at a time whisking them together to prevent too much fizzing.
Once mixed well together grab some of the mixture and squeeze it together with your hand to see if it sticks together well.
Fill the 1/2 mold with the flowers slightly packed in.
Fill the other side and place it on top of the first side and press together.
Continue with the rest of the mix.
After setting for a few minutes try opening the mold and let the bath bomb set on wax paper or parchment to dry overnight.