Lets take a look as some overhead watering devices. With their disadvantages they still do the job and are very economical to buy.
Hand Sprinklers
There are many kinds of nozzles for applying water from a handheld hose. The most effective are those that break up the spray into a fine mist which softens the impact of the water on the plant and on the soil around the plant.
Rotating Sprinklers
The rotary sprinkler is commonly used to water lawns. Rotating sprinklers give both round and square-cornered coverage, and those with locking arms and adjustable nozzles provide excellent spot coverage. It is an inexpensive sprinkler but it often distributes water too quickly to allow the ground to absorb it. To avoid watering too quickly, alternately run and turn off your rotating sprinkler (10 minutes on and 20 minutes off) to give water a chance to seep in.
Oscillating Sprinklers
Oscillating sprinklers sweep back and forth, giving broad coverage of the lawn the surrounding gardens. They water in a rectangular pattern or a fan shaped pattern which can be adjusted in size with some models. They are easy to move around in the yard. Their major limitation is that their high arc wastes water because up to 30% will be lost to evaporation before it gets into the soil. They also tend to distribute water somewhat unevenly. Those points at the edge of the pattern will usually receive the most water, with those spots closer to the sprinkler not receiving as much moisture.
Impulse Sprinklers
Impulse types hurl streams in a low arc and give even watering of large areas. They are attractive because the better models allow you to vary the amount of coverage from relatively small areas to quite large ones. They also allow you to vary the shape or pattern of coverage which is handy in yards with obstructions and/or funny shapes. Impulse sprinklers are the best devices for windy conditions because they throw water out low and flat, with great force.
