Question
what kind of potting soil is best to use for this plant when you trasplant them to a hanging basket

Answer
Hi Melina,
Thanx for your question. Hyponex, Miracle Gro and Scotts are fine brands of potting soils to use for your plant.  You should be able to find these brands at DIYs like Lowe's, Home Depot or at Walmart, Target, Kmart. I hope this helps.
Tom