Solutions: In minor cases of brown spot, there isn’t any need to treat the disease. However, if much of the foliage is affected and defoliation occurs, the plant will benefit from getting rid of the infection. It is recommended to start by applying organic treatment options, working up to the more potent synthetic, chemical fungicides if necessary. Organic options won’t kill the fungus, but will prevent it from spreading. Dissolve ½ teaspoon of baking soda and one teaspoon of liquid soap in a gallon of water. Using a spray bottle, spray on tops and bottoms of leaves until the mixture drips off. Repeat every two weeks until existing spots stop enlarging and new spots no longer appear. Spray a copper-based fungicidal soap on the leaves, coating the top and bottom leaf surfaces. Reapply as directed on the product label. Copper penetrates the leaf surface and prevents germination of spores so the fungus cannot spread. Apply an all-purpose fungicide to the entire plant, following the label instructions carefully.

Solutions: Like other fungal diseases, the progression of petal blight is extremely difficult to stop and impossible to reverse once it infects a plant. The best course of action is to remove all damaged flowers immediately and dispose of them entirely. Do not put them in the compost pile, where spores could grow and spread.

Solutions: There are several easy ways to remedy the nutrient deficiencies in soils. Use a water-soluble fertilizer. Fertilizers will include most or all of the macro and micro-nutrients the plants need to thrive. Adding some fertilizer to the soil will make those nutrients available and can combat deficiencies. Regularly apply organic fertilizer pellets. Organic fertilizers such as animal manures and bonemeal can supply plants with all the nutrients that they need to grow strong and healthy. Apply compost. Though not as finely tuned as artificial fertilizer, compost can nevertheless be rich in important nutrients and should be applied to the soil regularly. Apply nutrients via foliar application. In addition to supplementing the soil with nutrients, foliar fertilizer can be applied directly to the plant's leaves. Nutrients offered via foliar application are often taken up even quicker than those put in the soil, so the foliar application can be great for swiftly addressing specific deficiencies.

Solutions: For less serious cases when only a few leaves are affected, complete the following: Prune affected leaves. Using pruning shears, remove leaves that have spots. Dispose of these leaves to avoid spreading the disease to other plants. Clear debris. To stop the spread of disease, remove debris and weeds from around plants. For serious cases when many leaves are infected with large splotches: Apply a fungicide. Fungicides won't cure current infections, but they will prevent anthracnose from spreading to uninfected tissue. Apply a fungicide before a dry period following product instructions. Products containing copper diammonia diacetate are most likely to be effective.