Mix 1 part perlite with 3 parts well-draining potting mix. Jasmines need good drainage to prevent root rot.
Choose a container at least twice the diameter of the current container. Fill the new container 1/3 full of potting soil. Remove your jasmine from its current container and gently loosen the roots. If the roots are too dense, or have wrapped around the bottom of the root ball, slice the root ball from top to bottom on four sides.
Place the plant in the new container and add potting mix until the top of the root ball sits an inch below the lip of the container. Fill in around the root ball, tamping the mix down with your fingers.
Sprinkle 1 tbsp. of Epsom salt around the top of the container and gently work into the top of the soil. Water the plant thoroughly until water runs from the bottom. Do not allow the plant to sit in water.
Add slow-release bloom fertilizer pellets to the top of the soil at the rate of 1 tsp. per gallon of container capacity. Work the pellets gently into the top inch of soil so that it does not wash away when the plant is watered. Keep the soil moist, allowing the top inch to dry before watering.