Hana no iro mo tokiwa naranan nayotake no nagaki yo ni oku tsuyu shi kakaraba - Shui Wakashu(English Translation & Meaning)

花の色も常磐ならなんなよ竹の
長きよに置く露しかからば

Roma-ji: Hana no iro mo tokiwa naranan nayotake no nagaki yo ni oku tsuyu shi kakaraba
English Translation: May the blossoms' hue
also stay forever green,
if the dew that lies
on the slender bamboo's long joints
through long ages falls on them.
Meaning: May the color of the blossoms too stay ever unchanging, if only the dew that settles on the long joints of the slender bamboo through the long ages falls on them as well.
Commentary: Book Eighteen Miscellaneous Congratulatory Poems 1161

Headnote: "For a screen at the fiftieth-year celebration of the Kujō Minister of the Right, at a place where a flowering tree stands near bamboo"
The poet wishes that the color of the blossoms too might stay forever, if only the dew settling on the long joints of the slender bamboo through long ages would fall on them as well. The headnote shows it was written for a screen at the fiftieth-year celebration of the Kujō Minister of the Right, Fujiwara no Morosuke, at a scene of a flowering tree near bamboo. Laying long life over the evergreen bamboo and bright prosperity over the blossoms, it wishes that the blossoms, receiving the bamboo's dew, keep their color always, that is, that the glory of the one celebrated may long endure.
The author, written as "Motosuke," is Kiyohara no Motosuke. The father of Sei Shōnagon, he took part in compiling the Gosenshū as one of the Five Men of the Pear Chamber. He is counted among the Thirty-Six Immortal Poets.

First line, "hana no iro mo," means "the color of the blossoms too," pointing to the flowering tree beside the bamboo in the headnote, with "mo" carrying the sense of "like the bamboo."
Second line, "tokiwa naranan," means "may it stay unchanging forever," with "nan" a final particle expressing a wish directed at another. The poem breaks after this second line, and the lower verse gives the condition in inverted order.
Third line, "nayotake no," means "of the slender, supple bamboo." Together with the fourth line of 1177 in this book, "take no midori wa," it uses the unchanging green of bamboo for celebration.
Fourth line, "nagaki yo ni oku," is a pivot word: "yo" means the "joints" of bamboo and an "age." It layers dew settling on the long joints with dew settling through a long age. "Joint" is an associated word of "nayotake" in the third line.
Final line, "tsuyu shi kakaraba," means "if the dew should fall on them," with "shi" an emphatic particle and "ba" after the irrealis form expressing supposition. It sets the condition that the bamboo's dew fall on the blossoms too.
Author: Kiyohara no Motosuke
Source: Shui Wakashu
Prev Poem: Harubaru to kumoi o sashite yuku fune no yukusue tōku omōyuru kana
Next Poem: Yorozuyo o kazoemu mono wa Ki no kuni no Chihiro no hama no masago narikeri