Woody perennials often form roots when stems rest on the ground or are buried by gradually accumulating mulch. Make a new plant by simply cutting between the rooted stem and the mother plant. In this video, author and instructor Janet Macunovich demonstrates how to divide plants with woody roots.
Plants that have woody roots include candytufts (Iberis spp. and cvs., Z 5–9), euonymus (Euonymus spp. and cvs., Z 4–9), lavenders (Lavandula spp. and cvs., Z 5–10), sages (Salvia spp. and cvs., Z 5–10).