A Kumquat for John Keats

Today I found the right fruit for my prime,
not orange, not tangelo, and not lime,
nor moon-like globes of grapefruit that now hang
outside our bedroom, nor tart lemon's tang
(though last year full of bile and self-defeat
I wanted to believe no life was sweet)
nor the tangible sunshine of the tangerine,
and no incongruous citrus ever seen
at greengrocers' in Newcastle or Leeds
mis-spelt by the spuds and mud-caked swedes,
a fruit an older poet might substitute
for the grape John Keats thought fit to be Joy's fruit,
when, two years before he died, he tried to write
how Melancholy dwelled inside Delight,
and if he'd known the citrus that I mean
that's not orange, lemon, lime or tangerine,
...