Check the saucer beneath the plant for excess water. This may prevent your plant's soil from drying adequately. If the water in the saucer contacts the bottom of the soil it cannot dry out between waterings. Always empty the saucer after watering.
Insert you finger into the soil to a depth of 1 inch for small 6- to 8-inch plant pot or 2 inches for larger pots. If the soil remains wet for more than a few hours, you may have a problem with drainage. Your soil should feel slightly moist, but not soggy.
Remove the plant from the pot to check for water-logged soil in the bottom of the pot. Hold the pot with one hand while slipping the stalk of the plant between you index and middle finger on the other hand so your palm lies against the surface of the soil. Invert the pot and support the weight of your plant with you hand. Soggy soil at the bottom of the pot indicates over-watering or poor drainage. Repot the plant in fresh soil in a plant pot that provides good drainage.
Observe your plant for signs of over watering. These include leaf drop -- including new growth, wilting, dark mushy stems or failure to thrive. Mold on the surface of the soil or on the foliage indicates that the plant is receiving too much water.