You can use liquid plant fertilizer with a ratio of 5:10:5. Ensure the fertilizer you choose is slow-release to avoid shocking your succulent. Give it fertilizer in spring and summer, its growth seasons, and leave it unfed for the rest of the year. It is preferable to dilute the fertilizer using 50% strength soluble household food. Although you can fertilize your plant as many times as necessary, most plants can only be fed one time per year. The University of California, Davis says that the plant's sap can cause skin irritation and dermatitis to pets and humans.