We recommend before preparing soil for vegetables that you have your soil tested at your local extension service to see if there is something your soil is lacking in from the lists below. Organic material all vegetables need a healthy amount of organic material in the soil they grow in. Organic material serves many purposes. Most importantly, it provides many of the nutrients that plants need to grow and thrive. Secondly, organic material “softens” soil and makes it so that the roots can more easily spread through the soil. Organic material also acts like small sponges in the soil and allows the soil in your vegetable to retain water.