Certified GKH Gardening Expert
It really depends on the plants that you choose to grow. Carrots and radishes stay pretty low to the ground, but tomatoes can easily get 6 feet tall. If you are new to vegetable gardening, I suggest that you take a look at our vegetable gardening category: https://www.gardeningknowhow.com/edible/vegetables/vgen/vegetable-gardening-advice.htm
We have many articles on growing all kinds of vegetables.