The twelfth 節気 “sekki” division of the traditional Japanese calendar is:
‘blistering heat’ // ‘major heat’ (solar term)
The first “kō” microseason within this division is:
(きり はじめて はな を むすぶ)
“kiri hajimete hana o musubu”
Paulownia trees produce seeds
That makes 桐始結花 the thirty-fourth microseason of the year!
It typically lasts 23~28 July.
The other kanji are a bit tricky to interpret here…the hiragana paraphrasing makes sense though!
Image credit: SeedsForAfrica.co.za.