One of Japan's famous wagashi shops and tea rooms is Toraya and one in Kyoto it just a ten minute stroll from my home. It has a wonderful tea room and garden to let your gaze wander and is as tranquil and pleasingly minimalist as you would wish a tea house to be. Accompanying your wagashi you can choose a Matcha, Sencha or Gyokuru tea, served hot or cold. Matcha tea is made from powder, frothy and a little 'filling', in my opinion. Sencha is the classic Japanese green tea made from leaves. Gyokuru is an fine, fragrant and expensive type of tea. The last one is different from Sencha partly because it is grown in the shade in stead of the full sun. This one is a little more bitter than the Sencha I think.
Choosing a wagashi is done based on ingredients and appearance. Because that is what makes wagashi so special, apart from the fact that they are made mostly of natural ingredients. Wagashi are made to please the eye and accompany a good cup of refined Japanese tea. The wagashi however should be served or chosen according to the season. The knowledge of which wagashi to serve shows one's educational background.
Except to please the taste buds and the eyes, wagashi are said to please all five senses. Texture is one thing that is most important in wagashi, where the amount of moist plays a vital role. An other essential part of enjoying wagashi is the fragrance, which should be delicate and accompany the flavor and fragrance of the tea served with it. At last the sound of a wagashi is said to be the fifth sense it appeals to. This last one I did not experience, but maybe I'm not expert enough…
On a warm day I would advise to choose a cold Sencha with your wagashi, because of it's thirst-quenching quality and just overall wonderfulness. It also gives you a new experience than tea served hot, which you probably will come across more often.
Enjoying a cup of tea can take up to a hour if you take your time, which you should, and gives you an opportunity to enjoy a bit of 'Zen'. Try to concentrate on the taste of the tea and the wagashi, let your eyes rest on the garden and enjoy 'being'.
Toraya has an English website, for more information and addresses.