If you don`t want to lay irrigation pipes all over your garden, there`s an option I first saw here in Crete which may interest you.
Check out the layout of your garden and determine the highest point. Before planting out, dig horizontally laid channels, as many as you need to cater for your plants, creating mounds of soil in between the channels, (like you would for planting potatoes). Plant your veggies into the sides of the raised soil in between the channels. At the end of the channels, at the highest point of your garden, dig out a “feeder” channel, running along the top end of all of the horizontal channels. Into this “feeder” channel, you will introduce your water, either from hosepipe or well. Using the soil as “stoppers” or “dams”, you can direct the water into whichever channel you want to water the plants.