I also live in South Texas, and vegetables can be hard to grow or easy, depending on your soil. Looks like you wanted a self-irrigating system, which is something I know nothing about. But, I live right in the heart of the big city, and have an enormous patio garden. Everything except trees, and cactus is planted in containers - I even have huge ferns planted in old milk containers, so I can move them if we have a hurricane, flood, or a cold snap.

Why don't you start with a few simple things in containers, and learn what grows in your sun or shade mixture? Sounds like you have containers (or just go to the 99-cent store, and get the largest plastic pots they have. They have some large enough for small trees.) Make sure they have some holes in the bottom for drainage or drill some. Then, go to Home Depot, Lowe's or a local nursery, and buy bags of garden soil. I do not like the kind with Miracle Grow, but I get an organic mix called Black Gold. Get whatever you like, but sometimes soil with pearlite mixed in is good - it holds in moisture.

Start by planting a few simple things - Basil, tomatoes, zucchini, peppers, and some herb plants are available at just about every retail outlet - Kroger, Walmart, Sprouts, Home Depot, Lowe's, and all nurseries should have plants you can put right in the soil right now, and they will be fine. Try to give everything at least 3 or 4 hours of sun a day, but all day, all afternoon sun will be way too hot. Water every other day early in the morning.

Some stuff will die, but some stuff will live. Gardening here is easy in that we have a year round warm climate, but the heat can be overwhelming for plants - and gardeners, too. I've had begonias, palm trees, ferns, asparagus, ivy, jasmine, mint, lemon balm, and lots of other plants on my patio for the last three years, and it has survived floods, massive heat, and last year's surprise snowfall. The begonias never even stopped blooming.