eightfold gardenia; Gardenia jasminoides f. ovalifolia
A double-flowered variety of gardenia. Botanical/horticultural term.
I planted an eightfold gardenia in the garden.
梔子 is the common gardenia (Gardenia jasminoides), while 八重梔子 is a double-flowered variety.
Standard kanji spelling for this plant name.
Katakana spelling, often used in botanical or horticultural contexts.
From 八重 (やえ, 'double, eightfold') + 梔子 (くちなし, 'gardenia').