Cultivation of petunia

摘要

To make it possible to control the external view of flowers of petunias not by breeding but by only controlling cultivation environment, a method of cultivating a petunia having a colored portion and an outer margin in its corolla is proposed, which comprises controlling light quality of cultivation light in the daylight period after a seedling culture stage, in particular, after flower-bud differentiation until blooming to thereby control the proportion of the colored portion to the outer margin in the corolla. Especially, to broaden the outer margin in the corolla of the petunia, it is preferable to use yellow light as the cultivation light, and to narrow it, blue light as the light quality.