Like people, houseplants can contract diseases. Some are caused by bacteria, others by viruses or fungi. There are several diseases that affect houseplants. Here's a look at the most common and how to treat them.

Botrytis- Also known as Gray Mold, this fungus can be found on all parts of the plant. Begonias, African Violets and Cyclamens are particularly vulnerable to this disorder. Treatment consists of cutting away the affected parts and increasing air circulation. Remove any mold found on the soil, and spray the plant with a fungicide. Commercial versions can be found in any garden center, or you can make a homemade version by filling a spray bottle with water, a tablespoon of baking soda, and a teaspoon of vegetable oil.

Black Leg-This disorder affects stem cuttings and is caused by a fungus called Botrytis. The fungus invades the cutting and turns the base black. Affected cuttings should be discarded. To prevent, make sure your soil drains well and avoid over watering. Geranium cuttings are particularly prone to getting Black Leg.

Powdery Mildew- This disorder is found on the leaves of affected plants. It appears as a white powder on the leaves. Unlike Gray Mold, Powdery Mildew will not kill affected plants, but it will make them weak. To treat, removed badly mildewed leaves and spray the plant with a fungicide. To prevent, make sure plants have plenty of air circulation.

Leaf Spot- This disease is most often found on Dracaenas and Diffenbachias. It is characterized by moist brown spots that appear on the leaves. In severe cases, the spots merge and kill the entire leaf. Leaf Spot is caused by a combination of bacteria and fungi. The best treatment is to remove affected leaves, spray with a fungicide, and water sparingly for a few weeks.

Oedema-This disorder is also known as Corky Scab. It isn't caused by bacteria or fungi, but by the conditions the plant is in. It's characterized by hard cork-like growths on the underside of leaves. This is a reaction to being kept in low light and overwatered soil. Affected leaves should be removed and the plant should be moved to better light and watered less.

Damping Off-This is a rather common disorder affecting seedlings. A fungus attacks them at the base, causing the stem to rot and the seedling to fall over. To prevent, make sure your seedlings are in sterile soil, not over watered, and given good air circulation.

Root Rot- This occurs when plants are overwatered and the roots are deprived of oxygen. The roots literally rot away. The first signs are yellowing leaves and wilting. Eventually, the entire plant collapses. If caught early the plant can be saved. Treatment consists of removing the plant from its pot, removing the soil from the roots, and cutting away any roots that appear mushy and black. The plant can then be replanted in fresh, well-drainied soil. To prevent, don't overwater.

Viruses- There is no single symptom of viral infection. There may be stunted growth, deformed leaves and flower buds, and white streaks across flowers. Leaves will have pale green or yellow patches. Plant viruses are usually transmitted by insects or were already present when the plant was bought. Unfortunately, there is no cure. If your plant is showing signs of viral infection, throw it out. If you keep its pot, be sure to disinfect it thoroughly in a mixture of hot soapy water and bleach.

Fortunately most plant diseases are relatively easy to treat. Better yet, they can be prevented entirely by providing your plant with ideal growing conditions. If you do find signs of disease on your plants, act fast and follow the tips above and you stand an excellent chance of saving it!