(Consolida maggiore - Borragine maggiore)
Being hardy plants, they can be used in gardening to fill easily unimportant or secluded areas. But as well as plants that self sow, easily become invasive and, being very deep, root system are difficult to eradicate. In the basement are also always a few small fragments of root are still capable of producing new plants.
You can simply divide some piece of root and transplant elsewhere. It is easy, has a very high percentage of engraftment. I'd do it in the spring when the plant is still at rest. But in the meantime you can see on the soil the new shoots from seed, and eventually transplant them. This operation should be much easier.
In any case, I think you can split it at any time, even several times a year. But think well, maybe you do not want to find the garden invaded by this plant, then very difficult to remove.