The landscape around my home may be dreadfully bleak and somewhat shabby, but at least a gardener doesn’t maintain it. While inspecting trees for local tree care companies, I visit landscapes that are maintained by gardeners at many residential sites and a few industrial sites. With only a few exceptions, such landscapes exhibit particular innate problems that should be corrected by the gardeners who cause them. In fact, about half of the arboricultural problems that I routinely inspect have been caused by improper maintenance.
Many garden enthusiasts perform all the procedures necessary to maintain their gardens. Some of us employ gardeners to simply maintain the lawn. Others want other chores attended to as well, such as shearing of hedges. Regardless of the extent of the tasks assigned, maintenance gardeners often require some maintenance themselves.
Excessive irrigation is the most common innate problem among trees within landscapes maintained by gardeners. Some landscapes are so saturated that puddles linger long enough for algae to grow! No kidding; I must wear boots 
without tread to avoid leaving such sites with bits of the lawn attached. Saturation of the soil indirectly promotes development of shallow and buttressed tree roots by inhibiting development of deep roots. Excessive moisture promotes decay among mature roots, particularly among roots of old native oaks that had not been subjected to irrigation prior to installation of the landscape.
Irrigation is so often excessive because the problems it causes are not as apparent as desiccation that may occur if irrigation is insufficient. For example, clients may not see shallow roots or decay below the surface of the soil, but cannot miss a brown lawn.
An irrigation schedule cannot be prescribed, but must be determined by the unique environmental conditions of each site. If the shallow root system of lawn necessitates frequent irrigation, it should not be applied so generously that the soil is continually saturated. Areas that are landscaped with more deeply rooted species certainly do not need to be irrigated as frequently, so should not be assigned the same irrigation schedule that lawn requires, as is typically done by gardeners.
Gardeners are generally very efficient with lawn mowers, edgers, blowers and most of all, the dreaded hedge shears. They seem to compete by shearing species that are less conducive to shearing than those that their colleagues have previously sheared. Consequently, many items that should develop into small trees, vines or freeform shrubbery are indiscriminately sheared into rigid nondescript forms. Clients may need to protect some of such items so that they may develop as intended. An ‘efficient’ weed-whip is not as common but can be fatal.
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