13 Ways to Handle Houseplant Problems

Problem: White spots that look like powder or flour on your houseplants. Solution: This is probably a fungal disease, powdery mildew. Increase the air circulation in the room, and avoid overwatering. Saturated soils and poor ventilation are breeding grounds for this problem. Remove badly infected leaves, and if the problem persists, look for an organic fungicide labeled safe for indoor use. Follow all label directions. Shown here: a vining Philodendron, 'Brasil'

Problem: Swarms or clouds of tiny white creatures fly into the air when you move your plants. Solution: You’ve got whiteflies, insects related to aphids that suck plant juices. They make a sticky substance called honeydew that can attract fungal diseases. Spray the plant with an insecticidal soap, following label directions. You’ll probably need to re-treat. Some gardeners use a homemade spray of 2 parts rubbing alcohol, 5 parts water and one tablespoon of mild liquid soap. The good news is that some houseplants, like this red Anthurium, are seldom troubled by these pests.

Problem: Lower leaves turn yellow and drop. Solution: Several issues can cause foliage to turn yellow and fall off. First, be sure you’re not overwatering or underwatering. To check for signs of overwatering, gently ease the plant out of its pot and look for rotting or blackened roots. Leaf drop can also result from insufficient light, so try moving your plant to a brighter spot. Finally, make sure you’re using the right fertilizer for your plant, and feed as directed on the label. This Zamioculcas, or ZZ plant, seldom has these kinds of problems. It's tough enough to tolerate low light and little water.

Problem: Few or no blooms. Solution: Your flowering plant may need more light. Try giving it brighter light, such as an eastern exposure, or put it in a spot that gets more hours of light each day. Be careful not to give it direct sun, however; windows can intensify sunlight and cause leaves to burn. Orchids with few blooms may take a little more diagnosis. While they might need more light, they may also require a drop of about 10 degrees F. between day and night temperatures. Some need a rest period between bloom cycles, when you cut back on watering and stop fertilizing. Check with a local orchid grower or nursery for more advice.