Proper watering techniques are essential to the health of plants in the garden as well as in containers. In general, it is far better to water less frequently for longer durations. Frequent drenches can result in root-rot and attract moisture-loving insects. Frequent, shallow waterings are deceiving, as the deep roots will die and leave the plant with no drought tolerance or long lasting endurance.
Water pressure should mimic rainfall and not blast flowers or leaves unless the goal is to clean off bug infestations. Plants, in general, prefer not to get sprayed, but rather to receive the water at the root zone where they need it. If sprayers or some sort of overhead irrigation are your only options, then you must be careful to avoid inadvertently creating the constant moisture in which fungal diseases thrives. If you have to water with spraying methods only, water early in the morning, so that, like dewfall, the excess spray moisture on the plants will have all day long to dry out. Over or under watering will quickly expose weak spots on plants where pests, fungus or disease can enter. If not treated soon after, plants can experience stunting, dieback or death.
Proper drainage is essential and specific to each species. Become familiar with a plant�s needs before planting. Siting a plant in the proper soil mix will allow watering to encourage the maximum root depth and become more drought tolerant. Proper watering will keep beneficial micro-organisms present in the soil and allow amendments and fertilizers to become available to the soil which then feeds the plant. Soil texture is also important as plants in clay soil will not dry out as fast as plants in sandy soil, which usually require more watering.
Containers should be monitored carefully. When watering plants in containers, water the sides of the pot as well as inner areas to prevent an air/dry gap from forming between the container and the soil. Regular, full waterings at longer and less frequent intervals will promote plant health and vigor.
Ground watering should happen twice a week for a half hour or drop back to once a week for an hour if conditions are safe to do so. The general rule of thumb is an inch of rain a week. While watering, take note as to how far the branches or fronds of the plant extend. This is the rain drip line of the plant where lots of root activity takes place. The roots can be expected to grow out way past that circumference if the soil is not compacted. Plants requiring more nutrients and water will require heavier, longer waterings. For instance: trees and shrubs in grassy areas require more fertilizer and water than trees and shrubs planted in groundcover beds. Consider altering cultural practices and remove the grass around trees out to the dripline to improve the health and vigor of the tree and to save on watering bills.
