I just planted 25 green giant arbs along my driveway and decided to run 1/2 pvc along the tree row. I drilled 2 1/16" holes at each tree and capped the end line with a threaded cleanout. It is on a slight downhill grade. I found that I have a 2' high jet coming out of the last few holes which gradually tapers down to nothing for the first 5 trees. I know this system is not ideal, but It was an after thought and only has to last for about a year to get the trees established this fall and then in the spring time.

My idea is to place two PVC ball valves in the line to divide it up into thirds and use the valves to regulate the flow in this long line with both valves shut halfway. Does anyone agree or disagree? Is there a better solution that anyone has found to this type of system. Would a few pressure regulators be better?

Many thanks for any advice anyone may have!!!