I just came back from the nursery where I bought 4 kinds of petunias: "waves" in 2 colors, Supertunias, and Petitunias, plus the ordinary kind sold in 6 packs. The "waves", the Supertunias, and the Petitunias are all for hanging baskets. The ordinary ones are for bedding or deck pots. (will ordinary petunias cascade too?)

Can anyone tell me how many to allow for each basket? The baskets are ordinary sized (10"?), and each of the petunias came in a 3 1/2 inch pot (the waves came in their usual kind of 6-pack). Each basket will be mostly petunia but will/may have one accent like a Osteosperma in the middle. (I'd probably save money if I just bought the pre-made baskets: but I always want to do everything MYSELF...)

Thanks!