Let's think this through. If the rows run north to south, then tall plants can be planted at the northern end of rows and not shade the rest of the vegetables. If the rows run east to west, tall plants will shade what is north of them. However, this is really more of an issue if you are planning to grow vegetables in the winter because the angle of the sun is low in winter. It’s up to you. You can make either way work.

The OSU Extension publication, “Vegetable Gardening in Oregon” provides detailed information about what to consider when starting a vegetable garden.