The soil with the highest water-retaining capacity is clayey soil. Clay particles are very small and have a high surface area, which allows them to hold onto water molecules tightly. The spaces between clay particles are also very small, which means water has a harder time escaping the soil once it's absorbed.
In contrast, sandy soil has large particles with larger spaces in between them, which means water can easily pass through and drain out. Loamy soil is a mixture of clay, sand, and silt, so it has some water-retaining capacity, but not as much as clayey soil.
Stony soil, on the other hand, typically has poor water-retaining capacity since the stones take up space and leave fewer spaces for water to be retained in the soil.