The same, only different. There is a great difference between the roots of a soil plant and those of a hydro plant. That is clearly evident from this Dracaena marginata. The roots of the soil plant grow around the inside of the entire pot in search of nutrition. By contrast, the roots of the hydroplant grow straight down to get their nutrition from the water. However, the roots do not stay in the water but hang just above it. You can see that clearly in this photo. The space between the bottom of the roots and the bottom of the pot measures two centimetres and is filled solely with hydro clay pebbles.