Powder mildew is a common houseplant disease. If your plants are covered with a powdery substance that can be removed with a cloth, it's likely they have come victim to powder mildew. You can help to prevent this disease by making sure your plants get enough water and enough light.

You can treat this condition simply by removing the mildew with a cloth and applying a substance known as mildew-cide. Place your sick plant in a place where it can get more light and make sure you prevent the soil from becoming too dry.

If the leaves on your plants develop brown spots, it may be a sign of under or even over watering. Leaves can develop a fungus that is caused by incorrect watering. Be sure to educate yourself on the watering needs of your plants and provide them with enough sunlight. This illness will typically correct itself without chemical treatment if you being a proper regime immediately.

If leaf spots are concentric circles, your plant may have a fungal infection. You should remove dead leaves and allow for adequate circulation. Don't allow water to remain on leaves for very long, as this is breeding ground for fungus. And for additional treatment, use a fungicide. You can purchase this at any garden store.

Leaf spots may also be caused by a form of bacteria.

Yellow halos on your plant's leaves may be signs of a bacterial infection. These spots will swell to a "blob" if the plant is kept wet. Dry versions create brown spots and the leaves will look "speckled". Keep your plants in the right climate and give them room to spread and grow. You may also treat this ailment with bactericide.

Stem rot is another problem induced by watering error. In addition to rotten stems most overwatered plants like the show falling leaves and yellowish stem edges. Fungicide will give you quick relief but to prevent this problem from recurring, you should educate yourself on proper watering technique for that specific plant.

Excessive moisture in soil can cause root rot. Soil houses bacteria all the time, but if the soil they inhabit is chronically too damp, the levels of bacteria can grow to dangerous levels and attack the roots of the plant. The Zamioculcas Zamiifolia plant for instance will exhibit telltale signs like browning leaves that don't feel dry and wilting stems. The best treatment for this illness is preventions as very few plants like the recover from root rot. Most of them do eventually die of the problem.

Make sure your plants are healthy from the get go by educating yourself on the proper care for specific plant types. Use sterile soil and keep an eye out for budding (no pun intended) problems. If you do suspect an issue, treat it early and thoroughly.