Something is wrong with your plant. The leaves of your petunias are riddled with holes or your tomato plants have wilted. Your lawn is full of brown spots or the leaves of your houseplants have brown tips. What should you do?
Diagnosing plant problems can be a difficult task. There can be many different causes for any given symptom and not all of them related to insect or disease organisms. Most problems are due to cultural and environmental issues.