Follow instructions on container before mixing chemicals.  Never use the same sprayer for herbicides and insecticides.  Always wash the sprayer thoroughly before mixing any different type of chemical in it. Prune flowering shrubs and trees AFTER they bloom. deciduous trees and dogwoods while they are dormant. hollies most any time; however Summer pruning of hollies that produce berries may reduce Winter berry production. evergreens in Spring after new growth to reduce size and maintain shape. Be careful not to wound trees or shrubs with mowers.  Disease or insects may infest the wounded area. Yellowing leaves can indicate too much moisture.  Check for drainage problems.  Raise the planting height if you spot any standing water. Do not apply fertilizer near the trunk of a tree or shrub.