A few loose ideas: 1. If you can source paper and cardboard in abundance (or possibly scraps of natural fabric, or even banana leaves or other large sheets of slowly compostable material....then try a complete sheet-mulch system for suppressing the running grass. This was the ONLY way to garden on any scale in the field of bermuda grass I spent years on in Georgia. Usually I would lay the paper, etc. out over the growing grass, covering it with some kind of top-mulch....even if an incomplete cover like clumps of pulled weeds, stalks, etc.. the point is to keep the wind from blowing the stuff around. Then punch holes through it and plant transplants right in it. Worked will for large vigorous transplanted things like tomatoes and sweet potatoes. But you have to do it EVERY year on bermudagrass land. 2. Biochar. Biochar is extremely valuable in hot climates where organic matter vanishes so quickly whether mulched or incorporated. There are many easy ways to make it, even in a hole in the ground. Then add urine if you can and use that on your soil for the most intensive gardens. The benefits of the organic matter will last much longer in the soil. 3. As others have mentioned, the hoe is a cutting tool and not a digging tool when used for weeding. I know that in Africa and elsewhere there is a tool that looks a bit like a hoe with a heavy wide blade and a short handle, used for most of the purposes that Europe and America use a shovel for. The Western hoe is long handled with a light, sharp blade and you sweep just under the surface of the soil with it, like sweeping a floor with a broom. The point is to cut the weeds off just at or below the soil surface. You should be able to do it for hours without getting tired, unless the weeds are very dense.