Unless you apply your stitches evenly across the whole piece, it's not uncommon for the edges to wow or buckle. A really easy way to correct this is to lay down repeated lines of stitching in the waste area of the edge in the region of the wow. A few passes are usually all that's necessary.

Good info...Thanks.

interesting. i never knew that/

Great tip, thank you.

I have wondered what to do. Does backing help or make it worse?

I use a knit fusible pellon on the back of my art quilts. It is light weight and easy to sew through with machine and hand embroidery and adding beading.

I would like to know more about landscape art. Your picture looks great ( as much as i could see, lol )
please post your pictures.