Answer:
Hydroponic gardens don't use soil, whereas normal gardens always have soil as their matrix.
Step-by-step explanation:
Hydroponic gardens receive a constant supply of water and nutrients in concentrations determined by the gardener. These run constantly by tubes where the plants are inserted and they uptake what they need by their submerged roots. On the other hand, normal gardens use soil as the matrix from where plants have to uptake water and nutrients.