There are many ways to water a garden and some will not only save you time and labor, but also will help conserve water. Here are the different methods, listed from most efficient to least efficient.
Deep-soak methods: Deep-soak methods use 50 percent less water for the same effectiveness as some other watering methods. They keep the roots moist and avoid wet foliage.
Drip tape/drip line: Drip lines have a higher initial cost for equipment and take time to set up, but once they are laid out, they are the most efficient in terms of water use and time spent on landscape maintenance. They usually only need to be turned on once or twice a week for about an hour or two at a time and can be set on a timer. They also can be concealed under mulch or soil.
Weeping line/soaker hose: These are porous hose lines. They are different from drip lines in that while a drip line has evenly spaced watering points, a soaker hose is completely porous so that water sweats out of it along the length of the hose. The slow soaking prevents evaporation and runoff, and a soaker hose is easier to move than a drip line.
Hand watering: The benefit of hand watering is that it allows you to water directly at the base of your plants. However, hand watering requires your labor and time each time you need to water.
Water wand: All around, the water wand is the most efficient and convenient low-tech tool for hand watering. It is a hose attachment extending as a solid pipe a few feet from the end of the hose with a breaker, which is a sieve-style nozzle, at its end. They provide a soft, rain-like stream of water, which is more gentle on the soil. Its extended neck allows you to water directly at the base of plants without bending over. Many water wands come with a pressure valve that allows you to change the water pressure at the flip of the thumb.
Watering can: The can has some of the same benefits as the wand, in that it allows direct-point watering and a rain-like stream of water. But a full watering can could be heavy to carry and will require more bending on your part to direct the water to the base of plants.
Unmodified hose: The problem with using an unmodified hose is that the single stream of water tends to remove topsoil, exposing plant roots, and since it has no pressure valve, tends to waste water.
Sprinklers: Sprinklers are convenient for broadcasting water over a wide area. But they are the least efficient method in the garden.
Portable sprinkler: The portable sprinkler is the least efficient of all the previously mentioned watering methods. Water is lost to areas that don't need water to begin with, not to mention the extra water lost through evaporation. Since they broadcast water on plant leaves, they also tend to promote plant disease on some vegetables.