Asagao wa asatsuyu oite saku to iedo yūkage ni koso sakimasarikere

朝顔は朝露負ひて咲くといへど
夕影にこそ咲きまさりけれ

Roma-ji: Asagao wa asatsuyu oite saku to iedo yūkage ni koso sakimasarikere
English Translation: The morning glory,
bearing dew of morning time,
blooms, or so they say;
yet it's in the evening light
that it blooms more beautiful.
Meaning: They say the asagao blooms bearing the morning dew—but it is in the evening light that it blooms most beautifully.
Commentary: Book Ten Autumn Miscellaneous Poems 2104

Headnote continued from the preceding poem: "On Flowers"
This poem says that the asagao is said to bloom bearing the morning dew, but in truth its beauty increases in the evening light. The surprise that a flower with "morning" in its name is most beautiful in the evening shows the sharpness of the poet's observation and wit. The Man'yōshū "asagao" is widely thought to be the bellflower, one of the seven flowers of autumn.

The first line, "the asagao," marks the theme; the Man'yōshū asagao is widely thought to be the bellflower.
The second line, "bearing the morning dew," describes its blooming.
In the third line, "saku to iedo," "do" is adversative: though they say it blooms.
In the fourth line, "yūkage ni koso," "yūkage" means evening light and "koso" is an emphatic particle in kakari-musubi with "kere" in the last line.
In the last line, "sakimasarikere," "kere" is the perfective of "keri," answering "koso," closing with wonder at its evening beauty.
Source: Manyoshu
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