here is a little better picture, now you know what me and my trellis look like.

Veggiecanner, your construction is different... but the height & string spacing are nearly identical to my own trellises. I would say that considering the structure & trees behind the trellis, you are probably right about shading in the back row. My recommendation would be to go with one row only.

Nice set up! I think I might disagree about not growing two rows. All the beans will vine around each other and the strings to get out into the sunny side, it's not like the back side will agree to stay in the background. One method of growing I use is a 6ft high piece of concrete reinforcement wire that has a natural curl from the roll. It's basically self-supporting, but I prop the two ends open in a C shape so I can enter the circle. I seed both the inside and outside circle of the support wire. It all eventually intertwines and finds the sun.

I agree with sack. Because of the slope of my land my rows all run east and west,if I planted up and down hill it would cause bad erosion. I plant pole beans and Christmas limas too on both sides of the trellis and get beans from all over.

I plant on both sides sometimes, and cannot tell any difference in production - plenty to pick on both sides, tho i sure can't tell which ones come from where when it is all grown in!
Another thing i like to do is to plant spinach or asian greens behind the beans or peas - this adds a little shade for them and they do not bolt so soon in the spring growing.
Glad

Violet......I would only use the galvanized conduit as a frame, and put string up for the beans to climb.
Veggiecanner......great pics! You could always try a second row and find out how it would grow. Or maybe just plant a few plants on that side, so if they don't grow, you won't lose much.
I'm wondering......off to the right it looks like a galvanized pipe trellis. What do you grow over there? Which trellis do you like more?

i've grown beans on both of the trellises. Both are good. One is just more movable than the other.

I do it on both sides too without a problem....I couldn't possibly leave one side unplanted...not in me to waste space...

Love your set up and your nice tidy garden...