The recent fad of removing glacial boulders from native Midwest prairie to create walls for urban wildflower gardens provides the context for thinking about how a theistic stewardship ethic addresses the environment. The three commands of Genesis 1 and 2 provide the basis for a theistic stewardship ethic, where God as the Creator/Landowner establishes humans as stewards to administer his kingdom. Contrary to the oft-repeated view that the injunction to rule over justifies a mere instrumental use and hence abuse of the environment, the command gives value to the biotic environment because the created has interests and thereby moral standing. Consequently, the environment must be considered in the for-whom of moral calculation. However, a theistic environmental ethic adds that the value of nature is neither merely intrinsic nor instrumental, but derives from the value accorded it by its Creator, who in seeing it function declares it good. The command to care for allows for sustainable conservation and human use rather than mere preservation. And the command to fill connects with the need to preserve and foster genetic and ecological diversity. Throughout we apply these commands to the case study about boulders and native prairie.