I've got a 1/2" line I'm going to be running to a gardening bed. There is a section of the yard where that line comes from that is pretty well buried with some landscaping features and I don't really want to dig into it. However, I'm going to be building some planter boxes along that edge where the line is coming from.

Where the line comes out of that landscaped area, will it create any issues if I put a t-fitting about 5 inches out from the border so that the line can continue on to the garden, but then take the top part of the T and go up about 3 inches, and then a 90 degree elbow to double back to where the other boxes are going to be?

In other words from the T-fitting going back, there will be two lines on top of each other only about 3 inches apart.

Just wondering if there is some water physics principle I'm not aware of that will cause flow issues if I do that.