Crowns should be just below or right at the soil line. “More woodland plants are lost due to deep planting than any other mistake,” says Edmund. In nature, wildflowers grow on top of the mineral soil in the duff of decayed leaves and twigs and their roots spread out horizontally, not vertically. Finish by mulching. This insulates roots, conserves moisture, smothers weeds, and looks nice too. Shredded bark, decayed leaves, and pine straw are good choices.