Euphorbia tirucalli, also called Fire Sticks, is another great succulent for this arrangement. Take a look at Crassula Perforata - String of buttons for another great addition to your trailing succulent arrangement. Before we discuss watering and how to deal with an underwatered string of pearls let's look at the most common causes. Ensure you establish the real The Browning of leaves cause should not be confused as too much light also causes the leaves to become brown. Too much heat can burn and kill the plant. You should also consider the size of your plant when watering.