Fertilizing shade trees
The main reason for fertilizing trees and shrubs in the landscape is to maintain reasonable vigor so that plants will be able to resist environmental stresses and pests. Trees and shrubs in a landscape may require little or no supplemental fertilization if plants are sited correctly, fallen leaves are shredded in place, nutrient containing mulch is used or surrounding turf areas are fertilized. Fertilization is not a panacea. Don't expect it to solve problems associated with careless planting, improper watering or poor drainage. Be certain that new trees and shrubs are suited to the climate and location.
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