To solve the weight problem causing the lamps to lower themselves you need to add a brace of some kind to hold the sections of the lampstand in place and keep them from lowering. The red rectangle could be a piece of wood, a pipe, a ruler, most anything rigid. The short blue lines are tape, string, cord, wire, whatever you need to attach the brace to the sections of the lampstand. Spread the section out to the angle that creates the height that you want the bulb at, attach the brace, and the lamp shouldn't lower itself onto the plants anymore. Btw, I think you've reached your limit on crying smilies.
Put a smile on your face, this ain't the end of the world!!!