Check this thread out!
https://www.rollitup.org/bugs/335046-grizzlys-guide-pulverizing-pests.html
WHITEFLY
Prevent: If there are whiteflies in your area, sticky traps will catch whiteflies quickly especially if colored yellow. Adult whiteflies are strongly attracted to the color yellow and will fly into traps before flying to your plant. Yellow paper covered in glue or sticky substance would work as well.
Identify: Whiteflies look like its bitty white moths, the adults have wings. The easiest method of detection is shaking limbs on your plants, if tiny moths fly away from under leaves you got some whiteflies. Eggs are also attached to the leaves along the underside. These pests also suck liquids from your plant much like the spider mite. Whiteflies begin attacking
marijuana plants from the top down and prefer to attack the weakest plant available. If you only find whiteflies infesting the top of a single plant, you've caught an infestation as it begins. Leaf damage from the whitefly almost exactly mimic the damage caused by spider mite attacks. The further damage progresses, the more strength and vigor the plant will lose.
Eradicate
Repression: The whitefly is a difficult pest to control given that all the adults fly. The best slowing measure you can employ is yellow sticky traps placed around your plants then toss them when full. This will only control adults who leave eggs and larvae behind constantly, traps will not eradicate your whitefly problem.
Predators: Encarisa formosa is a species of miniature wasp that only attacks whiteflies. This small wasp does not attack humans and kills whitefly populations by laying eggs on whiteflies. When hatched, the wasp larvae eats its way through the whitefly, literally devouring it from the inside out. Slow and painful, just like they deserve. 2 predators per plant should do the trick if the infestation is caught before it becomes severe. Repeat every 2 weeks until 2 weeks after whiteflies cannot be spotted. Ensure you clean plants and grow area thoroughly if you have sprayed against mites or flies as these treatments will also kill this wasp.
Manual Removal: Perhaps Mr. Miyagi could catch them all with chopsticks. . . . but I don't recommend you try.
Spray: Easily smacked down with insecticidal soap, natural sprays, or pyrethrum. Prior to spraying, remove any leaves that are more than 50% damaged and burn them. If you can't start a fire anywhere, heating them to excess of 140F/60C will do the trick. Whiteflies die easily, however they lay eggs prolifically and love re-infecting damaged plant matter. Apply spray against the whitefly at 5 to 10 day intervals until 10 days after whiteflies have not been detected.