OK first off the term 'hydro' has been used to categorize seedless bud of pretty good quality... but in all reality hydroponics is just a method of growng in a liquid medium rather than soil. You can grow schwag hydroponically just like you can grow dank.

Now if it was outside I doubt it was grown hydro(not to say you can't grow hydro outside). If they were seeds you just threw they were grown in the dirt. But yea you have to remember that Marijuana is a plant and thats what it does.. it grows(no sarcasm intended). Now the chances that the spot where you threw the seeds had adequate light and werent to bug infested.. that was just luck. Next year try it again. Throw handfuls of seeds anywhere where you think they'll get good sunlight and watch them grow!