Cliches become cliched because they're true. Flowering fruit trees, and all the stages thereof, are something the average Japanese takes note of. Maybe they take note of them partly because sakura = PAR-TY! PAR-TY! PAR-TY!, but the fact is that over there everything is geared to direct your attention to cherry blossoms. They're on the news regularly in season. They're in the poetry you learn in school. They appear in advertisements and songs with a frequency that no natural phenomenon does over here. Newly blossoming sakura, half-open sakura, falling sakura, 'snowstorms' of falling sakura- it's everywhere. (A long way down the list in order of frequency, I think maybe we use clouds and rain the way they use cherry blossoms ie as a concrete or metaphorical image. Still doesn't have intrinsic 'this is us' connotations.)
Blossoms occupy national attention the way baseball and politics occupy- well, the attention of my neighbours to the south, shall we say. (If anyone discovers something that can occupy the Canadian national attention, please tell me so I can ignore it = yer average Canuck attitude to anything.) You'll see people in February walking about the plum trees, remarking to each other in delight that *this* tree is only half in bloom but *this* one is all in flower. Well, and flowers too- can't go to a park in September without being accosted by rows of chrysanthemums with their heavy blossoms held up by plastic frames (which will remind you of Elizabethan ruffs or decapitated heads exposed to the public, depending on morbidity) or to Kamakura in December without pressing and persistent invitation to come view the peonies.
Mainstream culture just don't talk that much about flowering stuff here. Possibly the English are different. The English I know (that's specifically the English; the Welsh may too, but the Irish and Scots usually seem to be talking about something else) are much more aware of plants and birds and you name it than anyone but a determined gardener NAmerican; there also seem to be far more determined gardeners over there than here. *And* there's a literary vocabulary of plants and birds and small-spindly-what-I'd-call-weeds to draw on, just as there is in Japanese. OTOH I've never seen the English publish books about 'famous small-spindly-what-I'd-call-weeds in the Morte d'Arthur' to parallel the books about them in Heian lit and the poems of Basho.
Thus I, mainstream non-gardening city-child NAmerican, have a problem when I want to describe the plums and cherries in my own garden. 'Blossoms' sounds odd; 'flowers' get talked about more, but cherry flowers aren't flowers. '---- blossoms' itself sounds weird. I really mean sakura, and I really mean the sakura are saite iru-ing.
So while I know exactly what Kenren means in his exhortation to bloom until you drop, there's no way to convey it in that exact metaphor. I rack my brains and finally figure that possibly our equivalent figure- sans cultural baggage- is that of blazing until you burn out. "Burn always with this hard, gemlike flame", should you not wish to be a meteor. 'Burn- burn- burn till you turn to ashes!' or 'glow until your flame goes out' is what Kenren's saying. Except, you know, not. Fire consumes and destroys; at best it illuminates until the dark returns; but blossoms are beautiful and delight until they fall in silent harmless drifts. There's a difference.