Really dumb question about machine quilting borders
 

I am doing my first (last?) machine quilt using a top pieced together by my Grandmother. it's sort of a modified
snowball design with a dark green border. I was planning to use white quilting thread because all of the fabric except the border are light. But here's my dumb question. If I use white thread to quilt the interior, what do I do when I come to
the border? I was told to make sure I sew over the border so the binding will cover my thread ends. On a hand quilt I would just do some design on the border in green. Any idea? Has anyone ever been thrown off this board for stupidity?

not stupid at all :) This is a design decision. If you like to have your quilting thread show, just continue with the white thread. Otherwise you can change to green thread for the borders.

You can work within the border area first with one color thread then switch to the interior area of the border that has the green color and switch again. For thread ends you can take a few stitches in place to lock the threads and/or leave long thread tails and when you are done use a needle and by hand "bury" the ends back into the quilt. That is if I understood your question. A photo would be very helpful.

are u machine quilting with long arm or domestic machine. Are you doinh a specific design in the interior or will it be an all over design. Or do you plan on doing a border design. There are some details needed.
Are you doing an all over that extends into the border to the edge or as separate design as indicated above.

When you are quilting by machine you will sew off the edge of the quilt border into the extra batting a few inches so that when you trim the quilt to size there is quilting holding down the entire quilt. This helps to stablize the edge of the quilt for attaching the binding.

If I do a quilt that doesn't have alot of quilting at the edge, after I finish the quilting I will do a basting stitch around the whole quilt edge to hold it in place before I trim it to size. I use the walking foot for this. Hope this info helps.

If you are planing to use 2 colors, do the whole center of the quilt first and then the border. This all depends on what pattern you choose.

EDIT: I keep reading your thread and have more to say. You can do the border design in white if you want to. It will show and it may look cool. Is your border pattern different from the main body of the quilt or is the pattern an all over one?
peace

I sometimes quilt my border with a matching thread. I do that because I am not the world's greatest quilter. I am sure that whatever you choose to do, your quilt will be beautiful.