Answer: Tea can be made from a huge variety of plants ranging from small annual plants to trees and their fruits. Some are considered purely as culinary teas and some are considered to be medicinal in value. To learn about a broad assortment of such tea plants and their uses, you might consult a good book on herbs such as "Herbal Bounty" by Stephen Foster.
I great source of seeds for various herbs is Richters Herbs in Canada; ph# 905-640-6677; web site: http://www.richters.com; their catalog is very informative, and lists lots of tea herbs.
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