My marijuana plants have been infested with whiteflies. Any advice? Can they do any harm to my marijuana? There are so many…
Whiteflies are around an eighth of an inch long and are solid white. When you shake the marijuana plant, they will fly off. When they’re on the plant, they pierce it and suck out is juices. They are also disease carriers and produce a gluey, sugar-like concentrate of plant juice that tends to invite mold. Whiteflies can reproduce at a rapid pace, but there a number of ways to get rid of them.
The easiest method is to bring a parasitoid. Encarsia formosa is parasitic wasp that will plant its eggs in whitefly pupae. Whitefly pupae are located underneath leaves, and when the wasp eggs are laid, the pupae turn black and die. These wasps do not make nests because they aren’t social. They are also so small that it’s more than likely that you won’t see them ever again. They live their whole lives off the backs of the whiteflies, and it only takes a couple of weeks to control them. It may be best to bring the population down with insecticides prior to introducing the wasps.
Derived from a plant similar to chrysanthemums, pyrethrum is highly effective at killing whiteflies. It comes in spray or bomb form, but the spray doesn’t do much to kill the eggs. Thus, it should be sprayed once every 3 days to get the bugs as they enter adulthood.
Botanigard is made up of a fungus that attacks and kills many different insects. When insects contact Botanigard, the fungus will attach itself to the insect’s body and kill it in a couple of days. The fungus is only interested the bugs; not humans or pets. You can buy it in a concentrate and just spray it on your marijuana plants.
Cinnamite is taken from the oil of cinnamon and is an effective insecticide or miticide. It is also fine for humans and their pets.
Pyrethrum is also effective for eliminating thrips, but it’s fatal to cold-blooded animals and other invertebrates like fish and reptiles. Humans and other warm-blooded animals are unaffected.