What type of sprinkler would you recommend for 8' diameter bed areas containing annuals with flowering pear trees in the center? There are 4 on each side of the driveway and will be on separate 1" mains teed off a 1" main at 50 PSI off of a submersible pump system. Should I put a backflow valve prior to the T or put one on each after the T? Also, we are in PA (southcentral)and our freeze line can get down to 24" during bad winters. Do you recommend that all mains and laterals at 30"? It seems that the system will have to be blown out in the fall no matter what depth unless drains are installed on every sprinkler. Is this correct or is there another solution? Also does the valve boxes need to be the same depth as the main line and if so are there boxes made this deep for a cover near the sod surface? Thanks for any help!! [
]