You ever eaten Potassium Sulfate or Potassium nitrate? Plants and people need totally different things
Plants don't just abrosb things and store it...there is more to it
Depends on your detector. Low power = only pick it up when its too late.
Re laser- www.laserstar.co.nz - Laser jammers work well, if you want a laser star one let me know, work well on bikes also
That will only save you from speeding in 50kmh area's which is silly
Also one that displays the freq is helpful to tell if its a cop or not and watch out for those new low power speed camera vans