The opposite of being in flower is wilting or withering. When a plant is wilting, it is no longer able to sustain itself due to a lack of water or nutrients. As a result, its leaves and stems may droop, and its flowers may close or fall off. Withering is a gradual process that occurs when a plant is no longer able to maintain its shape or color, and it eventually dies. The opposite of a flower could be a bud or an unopened flower, which are both in the early stages of development. Alternatively, a plant without flowers may be referred to as barren or sterile.