That is the stereotype - now the reality. Although there is no large "Central Park," even in the central parts of Tokyo you will in fact find some nice greenery. The city boasts many small parks, which often originated in the gardens of Edo-period daimyo. It seems that in the Edo-period Tokyo even was a veritable green garden city. In addition, in the last century, new parks have been laid out in the (then) less populated western part of Tokyo. And surrounding areas, as Kamakura, are still very green, so it is not too difficult to escape all that gray solidity.
If you want to know where to find the best flowers / in the best gardens / right in season, there could be no better guide than Sumiko Enbutsu's A Flower Lover's Guide to Tokyo. Ms. Enbutsu has already written four other guidebooks about Tokyo (and one about Chichibu) and is an expert in the various cultural and historical aspects of the city.
A Flower Lover's Guide contains 40 walks in Tokyo and places around the city. They have been organized under the headings of fifteen flowers and trees, starting with cherry blossoms in late March - early April and ending a year later with the camellia. The journey in between takes us along the azalea, tree peony, wisteria, iris, lily, lotus, morning glory, bush clover, chrysanthemum, maple, pine, narcissus and plum blossom.
Every chapter starts with an introduction about that particular flower, its history in Japan, and its associations in literature and art. These are the most interesting parts of the book and Ms. Enbutsu has unearthed many fascinating facts and episodes.
The walks take us to famous places, as Chidorigafuchi in Tokyo for cherry blossoms, or the Ueno Toshogu Shrine for peonies, but also thankfully to lesser known spots, so even for people who have been rambling around Tokyo's parks already, there is still enough to discover with this book in hand.
Take for example the plum blossom: I have written posts about the Yoshino Baigo in Ome (Tokyo) and the Atami Baien in Saitama, but Mrs Enbutsu suggests the Keio Mogusa-en Garden and the Ikegami Plum Garden, which are both new to me. When I visited the Sakitama Fudoki no Oka Park with its ancient tumuli in Gyoda, I didn't know there was also an "Ancient Lotus Village Park" nearby (in this case it did not matter, as I went there in deepest winter!). And although I was familiar with the trumpet-shaped morning glories sold at the famous summer fair in Iriya, the henka or "changed" morning glories grown as a game by dilettantes in Edo and now still on view annually in the garden of the National Museum of Japanese History in Sakura, were a revelation to me! And so on...
What is more, this guide book has been most beautifully edited: it has been lavishly illustrated with all-color photography by Michiru Unae, decorated with chiyogami floral designs and on all 40 walks you will have the support of large and clear maps and "getting there" indications.
In short, this is a perfect book that should grace the book shelf of every flower lover in Japan. And who doesn't love flowers?
A Flower Lover's Guide to Tokyo by Sumiko Enbutsu (Kodansha International, 2007)
P.S. As Kyoto and Nara are real flower paradises, much more than Tokyo, I am looking forward to a volume in the same format on the Kansai as well!