Starch and I bought the spray can when I first started...don't do it!! Expensive (at Jo Anns) and the nozzle broke before I had used half a can, bought another can and the same thing happened. Now, I buy mine at Walmart, Niagra in a a pump bottle for about $3.00 and it lasts about 2 quilts. Smells good too. There are a number of quilters that make their own and if they give a recipe, you could refill the pump with that and it might be cheaper but I like the convenience at Walmart.