Growing vegetables in sand is done using hydroponics--growing plants without soil. A water solution supplies the nutrients, washing over the roots of the plant, which is in a container. Sand in the container or mesh on top of the container supports the plant. If the soil is sandy, you can still grow vegetables by amending the soil heavily. The amendments add lots of nutrients to sandy soil, and sand drains well. Tomatoes, beans, squash and peppers all thrive in rich, well-drained soil.
Dig a trench 2 feet wide and 18 inches deep. Lay a 4-inch-thick layer of newspapers or shredded paper at the bottom of the trench The paper slows down the water from draining right through.
Fill the trench with a mixture of one-third sand, one-third compost and one-third topsoil or garden dirt. Add slow-release fertilizer per package directions. Mix all the ingredients well.
Continue digging trenches, laying newspaper and filling the trenches with the mixture of compost, sand and topsoil. The vegetable garden will be higher than the surrounding sandy soil because you've added compost and topsoil.
Plant the seeds at the appropriate depth. Most seeds will do well if covered with 1/8 inch of dirt. The exceptions are beans, peas and corn. Plant those 1 inch deep and six inches apart.
Water to a depth of six inches. Sandy soil drains quickly; even with the added amendments, the garden may need to be watered more often in dry hot weather. Check the soil by digging down three inches. If the soil is dry, it's time to water.
Fertilize the garden monthly.