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Why is my indoor plant dropping leaves?
Yellowing and dropping leaves can be caused by any number of factors which place the plant under stress. Too little water, too much water, too hot, too cold, too much light, too little light, insects and disease can all cause leaves to drop. To determine what your problem is requires keen investigation. If the plant is new or has been moved recently dropping leaves is very common. Plants taken from a greenhouse or well lighted area to a home which is darker often results in the plant dropping leaves. However, given good care, the plant should put out new leaves. Drafts from heating registers, doors or air conditioning can also cause leaves to drop. Inspect the soil. Is it too wet? Wet soils promote fungal root rots. On the other hand, if the soil is too dry, the plant will also drop leaves. In this case, water the plant or if very dry soak it in a bucket of water for 1-2 hours to thoroughly wet the root ball. Other soil related problems could be a lack of fertilizer which may give the plant an overall yellow appearance as well as salt build up in the soil. When water and fertilizer evaporates from the soil it leaves behind calcium and other minerals which form white deposits on the soil, pot or pot rim. This salt build up can result in leaves browning at the tips or yellowing and dropping off. The solution to salt build up is to leach the soil or repot the plant in new soil. "Leaching" is done by repeatedly flushing the soil several times with sufficient amounts of water to produce copious drainage. This should be done in a sink or outdoors to allow the water to drain away freely from the base of the pot.
Yellowing leaves are not always cause for alarm but they should prompt you to inspect the plant closely and determine what may be the cause. If obvious signs of insects or rot are not found, improving the cultural conditions of the plant is your best course of action.