Your mom was probably referring to hydro as not "natures" way of growing, which it isn't. It's a somewhat complicated system using no soil to grow. The use of water and chemical nutes, commonly.

Hydro doesn't mean it is super great pot. It doesn't create more potent smoke than organic soil grown. Hydro is good for spitting out mass amounts of cannabis in shorter periods of time. That's all it is, with a fancy name that came from Hydroponic gardening.