Answer: The bay leaves we use in cooking come from the plant Laurus nobilis. It is unfortunately not hardy in cold winter areas such as Pennsylvania, but it can be grown as a container plant and summered outside, wintered inside. It will become quite large and can be trained as a topiary.
It is usually available as a small plant through nurseries that stock herbs, or by mail order from herb specialists such as Richters. http://www.richters.com/
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