How absorbant are kitty litter and soil?
It depends on the quality of the litter. You should try different brands and see which works best for you and your kitty. You need to find the happy medium between liquid absorbance and odor absorbance. Furthermore, some litters, while being good for both the above, may tend to stick to the kitty’s paws causing them to leave a trail of the stuff around the house, which can be annoying. As for soil, I have no idea, but I don’t I would try that for you litter box. I answered this supposing you are going to employ these things for their intended use. If you intend to use them for something else altogether, please clarify further.