Which element is most critical in determining the selection of plants for a specific landscape?

Local climate conditions are essential in determining the selection of plants for a specific landscape because they directly influence the plant's growth, hardiness, and sustainability. Different plants have specific temperature, humidity, and precipitation needs, which are dictated by the local climate. For example, plants suited to a tropical environment will struggle to survive in a temperate or arid climate due to factors like frost, drought, or excessive rainfall.

Variations in sunlight exposure, soil type, and the effects of microclimates within a landscape also stem from the overarching climate conditions, further affecting plant health and longevity. When selecting plants, horticulturists must consider these local climate characteristics to ensure that the chosen plants will thrive, provide desired aesthetics, and contribute to the overall ecosystem.

While color preferences, availability of fertilizer, and the popularity of plants play roles in landscaping, they are secondary to the vital consideration of local climate conditions which ultimately determine whether a plant can survive and flourish in a given area.