Oklahoma Proven is a plant evaluation and marketing program designed to help consumers select the best plants for Oklahoma gardens. The goal has been to select plants that are tolerant of the varied and difficult environmental conditions found throughout Oklahoma. Consequently, using well-adapted plants should lead to greater gardening success and more environmentally-friendly gardens. Although the plants presented here are among the best for use in Oklahoma, this is just a place to start. There are many plants suited for use in Oklahoma and it is always imperative to match the environmental tolerance of the plant with the environmental conditions in a particular garden or even a particular spot within that garden. Oklahoma Proven plants have been selected to withstand environmental stress but remember that all plants need special attention during the establishment phase or during periods of environmental extremes.