Jobe's Organic Succulent Fertilizer Spikes. 2-8-8 formulation feeds plants at the roots, where they need it most. These organic fertilizer spikes, specially formulated for succulents, help build a nourishing environment that promotes beneficial microbial action where plants need it most at the roots. This in-the-ground feeding is the most efficient delivery system for organics. The premeasured spikes make for a fast, easy and mess-free fertilizing experience.