Gardeners who love to grow flowers but also feel a social obligation to conserve water will find it difficult to reconcile those two desires, according to Richard Y. Evans, an environmental horticulturalist at UC Davis. In general, the more leaves on a plant, the more water it requires, and not many varieties of flowers have few leaves, Evans says. Trees and shrubs can be pruned to reduce their size and, consequently, their need for water. If commercial flower growers are affected by possible mandatory cuts in water use, they may step up some of the conservation measures they've already begun to practice on a limited scale, such as drip irrigation, cutting back on watering, and recycling run-off water.