Onajiku wa totonoete fuke ayamegusa samidaretaraba mori mo koso sure - Kinyo Wakashu(English Translation & Meaning)

同じくは整へて葺けあやめ草
さみだれたらば漏りもこそすれ

Roma-ji: Onajiku wa totonoete fuke ayamegusa samidaretaraba mori mo koso sure
English Translation: If you will at all,
thatch it neatly in a row,
that sweet flag of yours,
for if the rains fall in disarray
the roof may well start leaking
Meaning: If you are going to thatch the eaves with sweet flag, do it neatly. If it lies in disarray when the early summer rains come, the roof may start to leak.
Commentary: Book Two Summer Poems 133

If you are going to thatch the eaves with sweet flag, do it neatly, the poet says, for if it lies in disarray it may leak in the summer rains. Playing on samidare as both the summer rains and being in disarray, the poem jokes about the custom of the Tango festival.
From poem 127 through poem 134 in this book come poems on the sweet flag, which was hung from the eaves and whose roots were compared for length at the Tango festival on the fifth day of the Fifth Month.

First line, 'onajiku wa', means if it is all the same, that is, since you are going to thatch anyway.
Second line, 'totonoete fuke', is the command 'thatch it neatly', and the poem breaks here. It contrasts with the sense of disorder in samidare in the fourth line.
Third line, 'ayamegusa', is the thing to be thatched, placed in inversion.
Fourth line, 'samidaretaraba', is a pivot word in which samidare means both the summer rains and sa-midaru, to fall into disorder.
Final line, 'mori mo koso sure', uses mo koso to express apprehension, lest it leak; koso closes on the realis sure.
Source: Kinyo Wakashu
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