23 Plant Requirements

Although plants established in cultivated gardens and landscapes are not the result of long-term evolution, the concept of “right plant, right place” can be effectively applied in these settings. Plant selection and placement that matches a species growth characteristics with existing conditions and available maintenance requirements supports healthy growth and vigor.

Cultural requirements are defined as site conditions that influence plant growth and longevity. Conditions typically include diverse combinations of light exposure, moisture conditions, soil types and nutrient availability, and hardiness zones. Depending on the site, conditions may also include plant tolerance for wind, salt, and drought. While garden plants require some routine maintenance for healthy growth, proper plant selection and planting practices decrease unsustainable maintenance inputs and reduce incidences of pest and disease and plant failure or death.

Maintenance requirements are related to factors that influence plant growth and development. Light exposure is typically classified as full (six or more hours of direct sunlight per day), part (four to six hours of sunlight) or part shade (two to fours hours of sunlight), and shade (less than two hours of sunlight per day). Water requirements and existing moisture conditions range from dry or xeric, to well-drained, and poorly drained or wet depending on the amount of rainfall or irrigation, the site slope, and the soil type. Soil drainage will be influenced by the amount and arrangement of particles of sand, silt and clay. Gravel or sandy soils tend to drain rapidly and have low nutrient levels because they are made up of relatively large particles with large pores or spaces between them.  In contrast, clay and silt soils are composed of tiny particles separated by minute spaces that tend to retain nutrients and drain more slowly. Garden loam that is fertile and well drained is the result of a balanced combination sand, silt, and clay.

Information from resources about plant growth requirements for light, water, soils and nutrients combined with knowledge of prevailing conditions and smaller-scale garden variations in temperature, air quality, wind, and humidity, and environmental stresses or pests and disease supports the identification of the right plant for the right place.