Combine flour, salt and cream of tartar in a medium wok.
Use a knife to chop up the rose petals. Mix them in with the dry ingredients.
Add water, rose water and vegetable oil and stir until combined.
Cook on medium heat, stirring constantly, until the mixture becomes a ball of dough that no longer sticks to the sides of the wok. This should take no more than 5 minutes.
Let cool for a few minutes, then use your hands to knead the dough until smooth. If desired, separate the dough into several balls and work in some pink food colouring with your hands. (Place the play dough in a sealed bag to prevent the food colouring from staining your fingers.)
Give the dough to your child to play with! Store each colour in a sealed zip-top bag when not in use.
Notes
To make this recipe taste-safe, bake the flour on a cookie sheet for 5 minutes at 350°F before using it to make the play dough. You can add rose essential oil for a stronger scent, but this will mean that the dough won't be taste-safe.