Albert Barnes Commentary 1 Kings 6:18

"And there was cedar on the house within, carved with knops and open flowers: all was cedar; there was no stone seen." — 1 Kings 6:18 (ASV)

Knops and open flowers - Rather, “gourds and opening flower-buds.” Imitations of the vegetable world are among the earliest of architectural ornaments. They abound in the architecture of Egypt and Persia. In that of Assyria they occur more sparingly.