Last year I built an under ground watering system for my tomatoes. Used 1/2 pvc and drilled small holes every foot on each side but off set the holes every six inches, stretched panty hose over the pipe and buried in between the plants about a foot deep. Put a 90 elbow on each end with a garden faucet attached. I hook up the hose to one end and open the other, if anything got inside the pipe the water flushes it out. I run it a few seconds and turn off the valve. I run it about 1/2 an hour until I see the ground starting to turn wet. Puts the water in the root system. With the wet weather last year I only ran it 3-4 times. h.h.