I have a large area filled with Senecio mandraliscae "Blue Chalk Fingers" that show large amounts of die-off. Typically, the base rots out and then the tops try to root down into the soil to start again. Large amounts of organic material from a nearby tree are regularly deposited into this area, and the soil is clay loam. What I think might be happening is that the organic layer is piling up and rotting out the base of the plant. This section gets hot sun daily, so there could also be water stress. Is there anything I can do to improve the situation?

Could I for example rework the soil with sand to make it more of a sandy loam, and hope that this improves conditions for the roots and lowers the amount of die-off? Once the soil drains better, then I could put more drip irrigation into the area.