Sandy soil washes out nutrients rapidly, you can mix in ground coconut coir or premade soil ammenders to help hold moisture and nutrients. I push superthrive for all plants to feed. 7$ a bottle, literally 2-3 drops per gallon is a complete feed and is easier to make and measure versus powder. I have never killed a plant using it...ever. One bottle will last years, and treat thousands of gallons. A few mods to your soil alone will make you grow like a champ alone. Sandy soil isnt a bad thing, just keeping the plant fed will make you a success. As far as easy starter stuff to build confidence...I say radishes, beets, carrots, squash, and beans greens(lettuce,collards,romaine) all are heat ,pest and frost tolerant, and are hardy for dryer conditions. Tomatoes I advise a bucket type of system, they respond faster to nutrients in the container, and can be moved to light sources. Strawberries can be done the same way, and its a superfruit for survivalists out there.