Occasionally, when I am in the process of giving an estimate on the upgrade or repair of a lawn sprinkler system, I am asked whether I will be using rotor or spray heads in a particular area and how many. Now while not everyone asks this, the ones whom do seem to have at least done some homework on the parts that make up a sprinkler system.
The answer is it is a combination of both depending on the needs of your lawn and landscape. Now when I say a combination, I DO NOT mean mixing rotor & spray heads on the same zone! I am telling them that rotor heads are for the larger turf areas and spray heads are for the landscaping beds or small grassy areas.
Rotory heads have a smaller precipitation rate than spray heads. This means they take longer to get the same sized area wet. Spray heads have a larger precipitation rate and will water an area quicker, also they “pop” up, they do not rotate like a rotor, which is designed to turn in order to water the larger grassy/ turf areas. This is why you NEVER mix rotor & spray heads on the same zone, as doing so will cause to to either over-water or under-water your lawn or landscaping.
If the water pressure allows for the spacing of heads 25 – 35 ft apart, then a rotor head should be used in that area. If you have poor water pressure and can only space heads 4-12 ft apart, a spray head should be used.
I hope this article helped you to understand why we use the heads we do in certain areas and the difference between the two.