Don't forget to heavy mulch your beds as well to retain the moisture and protect your soil biology. I just pull back a little mulch here and there when I plant.
Do ya ll use Onion sets or do you plant seeds? If you make starts do you use sand to plant your seeds in??
I live in South Texas, still picking tomatos, cabbage, serranos and cilantro from the winter garden. I have both earthboxes and an in-ground garden(about to add a second). I would recommend for your spring garden: Tomatos, onions, peppers(type according to your heat tolerance), eggplant, okra and green beans. I've already replanted my earthboxes with Tomatos, habanero and serranos, and eggplant. Depending on where you are, wouldn't hurt to get the ground worked up and your compost mixed in, planting time is pretty close in most of Texas.