CO2 Boost Plant Bags are a strain of mycelium that produces an abundance of CO2 without producing mushrooms. This means that when the bag is activated, the mycelium grows, eating the substrate it comes with, giving off heaps of CO2 straight into your garden, and it does all this for 9-12 months! Studies have shown that adding CO2 can increase yields by 30% and cut down harvest times by 18%! These bags work for all types of plants and can bring dying plants back to life.