I also changed the generation to 0.2. This made a huge difference. They are no longer and invasive menace to all living thing ;-)
plant_generation_options {
B:"Burst Plant"=2.0
B:"Chopper Plant"=0.2
B:"Creeper Plant"=2.0
B:"Fire Flower"=15.0
B:"Flying Flower"=2.0
B:"Helium Plant"=15.0
B:"Lightning Plant"=2.0
B:"Potion Plant"=2.0
B:"Propulsion Plant"=2.0
B:"Rain Plant"=2.0
B:"Repulsion Plant"=2.0
B:"Slime Plant"=2.0
B:"Squid Plant"=2.0
}
plant_generation_options {
B:"Burst Plant"=2.0
B:"Chopper Plant"=0.2
B:"Creeper Plant"=2.0
B:"Fire Flower"=15.0
B:"Flying Flower"=2.0
B:"Helium Plant"=15.0
B:"Lightning Plant"=2.0
B:"Potion Plant"=2.0
B:"Propulsion Plant"=2.0
B:"Rain Plant"=2.0
B:"Repulsion Plant"=2.0
B:"Slime Plant"=2.0
B:"Squid Plant"=2.0
}