Malabar chestnut (Pachira aquatica) is a tropical plant native to Central and South America. This evergreen can reach up to 60 feet high in its natural habitat, but grows much smaller in North America. It is often sold in pots under the name "money tree." These plants are relatively hardy but require regular watering and protection from extreme heat and cold. A variety of conditions can cause yellow or brown leaves on the money tree.
Money trees need regular watering but shouldn't be allowed to stay wet. Too much water can cause yellow leaves and the loss of older leaves. Overwatered money trees may also wilt. Over time, too much water can cause the roots to rot and even kill the plant. Water your plant around once a week, allowing the soil to dry between waterings. The California Rare Fruit Growers recommend less frequent watering during the winter months, especially for trees grown outdoors.
Plants that receive too little water often suffer from symptoms similar to that of overwatering. Too little water causes leaf yellowing and loss, as well as leaf wilt. Even if you water regularly, plants in overly small pots may not get enough water. Increase watering frequency or re-pot your money tree, then monitor its condition.
Leaves may turn yellow or brown if a plant gets too much sunlight or experiences a sudden change in light. Very hot sunlight can cause the leaves to scorch along the edges. Plants suffering from light problems may also lose their leaves or suffer from reduced growth. Consider moving your plant to a shadier location to reduce leaf scorch and yellowing.
Money trees require relatively little fertilizer. Use a balanced, all-purpose fertilizer during the warm part of the year. Apply this treatment lightly and no more than once per month. Too much fertilizer won't make the plant grow more. Instead, it may cause leaf burn, yellowing, light-colored leaves or even the death of the plant. Money trees do better with too little fertilization than with too much. If your plant has increased symptoms after feeding, reduce or discontinue your fertilizer application.