This is purely speculative because I've never tried it, but I think that it would be helpful to take root cuttings that leave a portion of the central disc still attached. Let me explain... Weldenia roots are like a starfish in shape. There is a central disk with tuberous arms going out radially. Instead of just taking snippets of pieces from the ends of the roots, it would he helpful to excise the whole rootlet along with a portion of the center. The plant's leaf growth emerges from this center portion so if you had a piece of it along with the root your chances of propagating the plant would be much better. The plant does not form dormant shoots in this central disc at the end of the growing season in the same manner that a Dahlia would form an "eye". The new growths with meristematic tissue arise spontaneously from the central disc when the plant starts growing again in the spring. Normally, the plant would have growth regulators that prevent more than one growth from emerging from this disc (this is why I imagine that Weldenia plants do not offset in the wild); but if you split the roots into several pieces you could get several new plants. This should be attempted during the plant's dormant period. The root cuttings as I described should be placed in a dryish sandy medium until the cut end forms a callus. In the spring or when the rainy season begins (whichever is first) the plant will hopefully form a new growth from the central disc portion attached to the rootlet. Good luck