Tea Grade, A to A+++++
The tea grade is separated mainly according to cost, production region, taste, quality etc.
The 1st level is A which means daily drinking tea.
For instance, one tea has several levels at our supplier in wholesale market. Then we will choose one level which can satisfy our daily drinking request. It should be healthy, enjoyable, good on storage, and economic. This varies on tea and supplier and generally it is around the medium level at our suppliers.
From then on, there are grades like A+, A++, A+++, A++++ to A+++++. The costs and prices from us will go up accordingly. The taste and flavor will be richer and there will be more plus for enjoying tea.
But green tea is quite different. Like Long Jing, Bi Luo Chun, An Ji Bai Cha, Mao Jian, Tai Ping Hou Kui etc. The higher the grade is, the taste will be more elegant. On many cases, you may find the lower level seems sweeter, more fragrance, more fruity flavor and easy to understand. It is not necessary to say you can take this as a golden rule to judge each green tea, please note that. On the contrary, try to compare them is always a golden rule to improve experience and knowledge.
On some tea, we may have only one or few grades like A and A+++ or A+ and A+++ or some other combinations. The reason is due to budget limit, we can't get whole collections. So we try to choose one or few combinations and the grade gap is huger, the better for our customer to learn about difference.
Above that, there are still S to S+++++ grades which are selected from core tea region, like Wuyi Yancha from Zheng Yan (core rock region), Hou Kui from Hou Keng etc. We don't intend to source tea of these levels but just when it is occasionally available and we can make sure of the source and quality. Even though, we may not stock much of them because of budget limit.
And sometimes (not each time), we can't tell much difference on blind test. (I mean, even one person is first to that kind of tea may know one is different from another, but when you know the price gap after that, you may wonder if you would like to pay for higher price one without hesitance or just get few for some important days because you just love this tea so much).