What is the most potent sedative herbal therapy?

Herbals : Kava and valerian are 2 that come to mind, because people use them to help with sleep. Often additional botanicals such as hops, passion flower, and lemon balm are used in combination as well. You should be aware that there have been some rare, but severe, cases of liver damage with kava.

Alt Med for anxiety: Agree with previous. Recent research and some experienced thought leaders in alt. medicine also encourage GABA, L-Theanine, and Rhodiola. First two not herbs specifically, but naturally derived supplements you can use. L-Theanine is in green tea and has a good safety record. Recommend Moyad, Supplement Handbook. All the best on your quest for health.