The Right Place
Sweet Woodruff grows as far north as the Great Lakes, upper New York state and into New England along the Atlantic coast (zone 4). It can withstand winter temperatures as low as -10F. It tolerates hot weather as far south as central Florida (zone 9), as long as it's in a shaded location.
Planting Nursery Stock
Plant sweet woodruff in a shady spot, with moist, well-drained soil. Though it likes partial shade, woodruff can handle some morning sun, especially early in the season before all the leaves appear on trees. It prefers moist, but well-drained average garden soil somewhat on the acid side (pH 6.0 to 6.8). Plant seedlings in the spring when the soil is dry enough to work with and frost danger is past. Loosen the soil in the bed with a trowel or hand rake down about 6 inches, breaking up large lumps and removing rocks. Smooth the soil surface. Dig a hole for each individual sweet woodruff seedling deep enough and wide enough to accommodate the plant's root system and soil ball. Carefully set each seedling in a hole, then fill it in with soil. Firm the soil gently around the stem and water. Space seedlings from 6 to 12 inches apart. They will fill in rapidly.
Sweet woodruff grows well as a potted plant indoors or out. Select an attractive container or use a window box. Line the bottom with a thin layer of gravel or broken shards of old flower pots to allow drainage. Cover this with 2 or 3 inches of potting soil, and then position the plant on top. Add more soil to cover the roots and fill the container to within an inch of its top. Tamp the soil down to firm the plant into position. Water thoroughly from the top, until excess water runs out of the drainage hole. Do not water again until the top inch of soil is dry.