Much as I love to hate the very idea of an official pronouncement about art, this one is so official, it must fit under the title of this thread!
The Japanese Ministry of Foreign Affairs takes pride in bonsai as a 'Pastime Art'. There's no pigeon-hole for 'Arts' without an attribute: http://web-japan.org/museum/menu.html
Perhaps it was down to Karma that the website remained in a permanently unfinished state [Hic!] despite haute patronage? The page seemed worth picking because the pigeon-holing act is fairly spontaneous. At the very least I would expect that the developers were as conservative as one might be expected for the job and did not deploy some quirky personal view of which things are Art.
Funny... Perhaps that situation is simply one of whatever fleeting kind when an answer - one answer, and only one - is mandatory for such a question? If the weight of dedicated paper is any sign, much of the fun must be in the asking: the matter of classification wanders through a wonderfully short, but intricate history of Aesthetics - as a species of philosophy - in Japan.
A few samples that happened to be in my way recently, bring up bewildering wobbles around familiarly European abstractions stranded in odd circumstances: “Unfortunately, however, even today we have not attained the truth of beauty […]. Yet, oddly, people who are confident enough to call themselves artists do not show any intention of offering an opinion as to what art is…” [Tsubochi Shoyo, What is Beauty? in Michelle Marra, Modern Japanese Aesthetics: A Reader, page 49]
I am mostly guessing that the cultural clash of restoration must have produced oodles of excruciating writings: there were honest attempts to classify European philosophy including aesthetics, and more feeding on the various incongruities... If anyone needs evidence for the well-worn saying that "no one is prophet in their own country" there is plenty to go around in the Meiji-onwards Japanese approach to western aesthetics! All in all, it may be that the ‘Pastime Arts’ were too tough to crack. Sounds familiar?