A thorough examination of your yard and garden in early spring can keep pests from reaching epidemic proportions later in spring or summer. This can save you time, expense, and unnecessary pesticide applications. An added advantage is that damage symptoms and other signs of pest presence are easier to spot before summer foliage and weeds make them difficult to see.
Many pests spend the winter as eggs on trees and shrubs, or in plant debris on the ground.
For example, if certain plants had pest problems last year, such as spider mites or aphids, early-season applications of horticultural oil can kill overwintering eggs. If spider mites were a problem in your yard last year, apply horticultural oil to the trees and shrubs that had the infestations in late winter or early spring before bud break. These tiny pests probably won't be active yet, but the eggs or the red or orange adult females will still be hidden in the bark of the plants. Adult spider mites are about the size of a period, or smaller. It will be difficult to see the eggs or adults, so just spray the plant if it had a problem last year.