Water properly

Watering in the morning is preferable for several reasons, but among them is that wet leaves have the opportunity to dry, staving off fungal diseases. Watering in the evening doesn't allow for foliage to fully dry, leaving plants susceptible to disease.

Promote air circulation

As your plants have grown through the spring and summer, you may notice that your garden has become quite crowded. An overcrowded garden hinders air flow and creates an environment ideal for powdery mildew and black spots. Consider pruning to promote better air flow and, if necessary, transplanting.

Watch for insects

Pests mostly annoy because of how they chew through plants, but some also bring disease into the garden. Aphids are well known for being among these pests. Using a combination of companion planting and organic solutions, such as neem oil or introducing competing insects like lady bugs, to repels pests, gardeners can eliminate many of the pest-related risks in their garden.

Cut off the disease

Sometimes the best course of action is to physically remove the disease from the plant. In some cases, disease can be contained by cutting off the infected stems; however, in more severe cases, the plant will need to be destroyed. Whatever the case, sick plants should be disposed of and not composted.