If you've ever grown cucumbers, you know they can get a little out of hand within a few days. One day you see a little cucumber growing and the next, it has ballooned into a hard dried out, inedible giant. If your garden receives a decent rain or you water, keep a special eye on your cucumbers as they seem to soak up the water very rapidly - sometimes growing at alarming rates. So the best advice I can give is to watch your cucumbers carefully and pick them while they're still small to medium sized and tender.
Cucumbers are a great candidate to grow vertically. They are natural vines and grow vigorously. Train the main vine to grow up a supported string or bamboo pole and trim off any extra vines. You can grow many cucumber plants this way in a small space.