Add the baking soda, epsom salts, corn starch, and citric acid to a medium bowl and stir with a whisk for 2-3 minutes, until completely combined.
Slowly add the sweet almond oil, drip by drip, while stirring with the whisk. Be careful not to pour too quickly and don’t stop stirring, as the liquid can activate the fizz.
Repeat the step above with the water.
Add the essential oils, while stirring.
Peel petals off the rode buds, and add a few to 9 of the heart mold cavities.
Spoon bath bomb mixture into the mold cavities, then press down with your fingers to pack them.
Allow bath bombs to set for about 4-6 hours, then unmold.
Wrap finished heart-shaped bath bombs in plastic wrap and store in a dry place or in an airtight container.