Houseplants add interest to the indoor spaces they adorn. Whether you choose your houseplants for their interesting foliage or because of their flowers, proper care ensures they remain attractive year around. Browning leaves are a symptom of a cultural problem or disease. While some browning and leaf death is natural, if all the leaves or a large portion of them are beginning to brown and die you must quickly find the cause or the whole plant may die.
Inspect the afflicted leaves and determine the amount of browning. Check if the leaf tips or whole leaves are turning brown or if the browning is occurring in blotches or spots.
Check the light requirements for the plant on the plant label or tag, especially if the leaves are browning in spots or blotches. Too much direct sunlight may cause burning and browning of leaves and damaged plants should be moved to a shadier area.
Stick your finger in the soil at least 2 inches deep to check for moisture. If the soil feels dry and whole leaves are browning, the soil is likely drying out too much between waterings. Water the soil from the top when the surface begins drying out. Add moisture until the excess drains from the bottom of the pot.
Stick your finger in the soil and if it feels excessively wet or if soil sticks too your fingers the plant is likely over watered. Over watering can lead to brown spots on leaves. Water the plant only when the soil begins to dry out and empty the drip tray after watering so the soil doesn't reabsorb the unneeded moisture.
Check the leaf surfaces for signs of fungus. Most fungus infections resemble gray or black fuzz or hairs and are caused by too much watering and lack of light. Check the light and water requirements for the plant and treat with fungicide if necessary. Turn on a fan near the plants to add some air circulation through the leaves, which helps eliminate fungus.
Check the undersides of leaves for signs of insect damage, especially if brown spotting has occurred on the leaves. Aphids and mites are the most common houseplant insect pests. Treat with insecticidal soap or a miticide.