I keep them in a Plastic tub with Chicken mash, oatmeal, and peat moss. I throw in small pieces of greens that I feed my dragons for moisture. They like a moderate room temperature 70-80 degrees. Cheaper to buy by the thousand, and the keep pretty well.
Supers are easy to keep. I put mine in shoebox sized rubbermaid tubs (or one size up) with air holes melted around the upper edge. I use wheat bran for the bedding and occassionally mix in some baby cereal and premade worm gutload from a local feeder company. I also put slices of potato on yogurt tub lids for moisture (I don't sit right on the bedding because it can make the bedding go moldy). Supers live for months easily as long as you keep the bedding dry and give them greens, apple slices or potato slices for moisture (they'll eat the bedding).
I've been feeding my almost 6 month old: crickets, phoenix, silkies and butterworms (alternating) but is it a good time to introduce superworms? Any drawbacks? Would be easier to buy in a store and not online with shipping. Somehow I thought she needs to be bigger. Also could keep a larger amount in a container.
You want your dragon to be about sixteen inches long before you introduce superworms. Once she's large enough, they can easily be used as part of a mixed and healthy dragon diet.