Knowing how to prevent and treat pest problems is fundamental to maximizing the rewards you can reap from your gardening efforts. When faced with a pest problem, gardeners ? new ones in particular ? often reach for toxic insecticides.

It's true that many poisons sold in garden centers will kill any, and often all, insects in your garden. But spraying chemicals is rarely the best strategy. Many pesticides are hazardous to humans and wildlife, and most will kill beneficial insects right along with the pests you're targeting. Before you march into your garden armed for an insect Armageddon, answer three important questions:

1. Will natural predators control this pest? In many cases the answer is yes, but you will never see your garden's defenses in action unless you actively encourage beneficial insects and adopt a wait-and-see attitude when new pest problems arise. Always watch what happens for at least five days after you see a pest become active, before you resort to insecticides.

2. Can you control this pest by using preventive methods? You can prevent attacks from many nonflying insects ? as well as diseases ? by rotating your crops (not planting them in the same place more than once every three years); by cleaning up and composting dead plants; by eliminating habitats such as weedy host plants; or by growing resistant varieties.

3. Are there easy ways to capture the pest or to install barriers that will protect the plants? Some insects are easy to pick off and drown in a pail of soapy water, or you can nab them with pieces of duct tape or a rechargeable vacuum. If you see a certain pest returning to your garden year after year, you often can protect your plants by covering them with lightweight floating row covers.