Of all the states that have cottage food laws, WA is one of the toughest.
However, dried teas are accepted (as long as the ingredients are from an 'approved source'...
...you may want to check with the authorities about using your home-grown leaves
before you pay the permit fees).
From the
WAC 16-149-120 (Allowable cottage food products), I have copied the following (see attachment) from the list of approved products.