I would define a plant pest Is anything causing problem in my garden. It could be a weed or an insect or a disease or an animal. My number one strategy is investing time walking around observing looking for things that I’m expecting and issues that might make me look closer for what is happening For example, when I look out to where my pumpkins are, I can see some leaves wilting I know that that’s a relatively new problem because during the last week there were no wilted leaves On closer observation, I see insect eggs And some mottling on the leaves. The next step would be to decide on a strategy in this case I intend to cut off the wilted leaves and see if that helps. It may be too late for any kind of pest control But I’m keeping a close watch on it now