I suggest you consider separating the two parts with some kind of an open fence, or trellis, combined with a gate - if your garden layout will accommodate it. We didn't want to see our vegetable garden all the time, so that's what we did - see these two pictures -

Click for vegetable garden side

Our garden will be separated by concrete and terracing. We have a inground pool with concrete around it.
so when you walk into our back yard you see the pond on your right, straight ahead is the pool and veggi garden and to the left is more formal japanese gardens and eating areas.
I used to have the garden in the back out of site, but was having problems with mold. There just was not enough sunlight there. This year I had to move it to the front of the yard, near the pool. my husband was thinking of a low fence. We really couldn't use a large fence because the area is not very big (like 250sq ft) We don't have as much room as you, I wish I did though. If we used a high fence we would block the sunlight getting into the small garden.
-renee

Renee - The shade cast by a fence varies with the seasons. In summer, a fence running east-west doesn't cast much shade at all. You can get an idea of how much a shade a 6ft fence will cast by just standing there (if you're a six-footer). It might be worth actually measuring it - you may find that your 250 sq ft would get more sun than you expect or that a (say) 5 ft fence would work.