This sounds like worm tower vermicomposting--but this is something that I wouldn't really try in brutal TX heat--in milder climates they can do this by putting the red wigglers in a heavily mulched raised bed. Our native Texas earthworms are not the best/fastest composting worms, they are better deep burrowing aerators--red wigglers are the best composting worms. In Texas, you can do outdoor trench red wiggler vermicomposting--and I do--but only in a nearly 100% shaded spot (especially March through October).
I have mine set up in 4' X 8' trenches, with 12 inch tall untreated lumber. I place about 6 inches of horse stall waste (manure, urine, bedding) or half decomposed compost in the trench for about 3 weeks, exposed to rain and elements. This allows any dewormer to deactivate from the horse manure. Then I add produce waste in one end section of the trench and cover entire trench with 6-10 inches of fall leaves, straw or hay and let it rot for about a week. This allows the microbial count to start in the bin (which is what the worms actually feed on). At this point, you can add your worms. I use black shade cloth to cover the entire trench (that is also in 100% shade). The shade cloth is very breathable--unlike a tarp or plastic.
The standard measurement is that a pound of worms can live in a square foot of vermicomposting space---but you would want to start at a much lower quantity, as worms can reproduce fairly fast. I would start with about 1/4 to 1/2 of worms per square foot.
I feed the worms one strip at a time, so that they migrate from one end to another, leaving the finished VC behind them for easier VC harvesting.
I would be happy to help anybody interested in this great way of composting, I can't say enough about how great the VC is for your gardening and waste reduction!