Select a planting spot in an area that drains well such as a rocky slope or elevated area. Avoid low-lying garden beds that tend to remain damp. Plant Senecio mandraliscae in an area that gets between two and six hours of sun a day.
Amend the soil in the planting area. Mix together equal parts peat moss, pine bark, vermiculite, sand and compost. Spread the mixture 3 to 4 inches thick over the planting area and work it into the top 6 to 8 inches of the garden soil with a garden fork.
Dig holes in the amended soil slightly larger than the nursery pots. Slide the Senecio mandraliscae out of the pot gently, so as not to damage the delicate stems. Place the plants upright in the holes and refill the soil around the roots.
Soak each plant until the soil is evenly damp at least as deep as the root ball. Water when the top 1 to 2 inches of soil dries out during the growing season between spring and fall.
Fertilize once in spring and again in early summer with a slow-release balanced fertilizer. Alternately, you can add water-soluble fertilizer when watering.