An herbaceous perennial native to Europe, this purple-flowered variety is the "true comfrey" of European herbalism. In addition to its traditional usage, comfrey also makes an excellent supplement in the feed of domestic animals. Comfrey prefers full to part sun with rich, moist, yet well-drained soil. Sow the seed just under the surface and tamp in securely. Sown directly in warm soils, germination usually occurs within 30 days. A 30 day period of cold, moist refrigeration followed by planting in warm conditions will noticeably speed up germination. Grow the seedlings out in pots for about three months, then transplant to the garden. To avoid the plants spreading, cut them back when they begin to flower, and mulch the crowns with the leaves.