Dear Dan, I have an infestation of whiteflies! I’ve been spraying with Einstein Oil 2-3 times a week and put sticky traps all around the indoor garden area. This is not really helping as the traps fill up quickly only to be replaced and filled quickly. I don’t want to resort to using a chemical bomb if I don’t have to. What can I do? – AppleBomb
Dear AppleBomb,
Whiteflies resemble tiny moths and the feed on the underside of plant leaves draining them of moisture, slowing growth and causing telltale slimy marks on the tops of the leaves. Typically, they enjoy moist conditions so over-watering and high humidity can bring upon outbreaks or exacerbate an existing infestation.
The oil you’re using can be effective if applied regularly and properly. Reapply weekly and be sure to get the undersides of the leaves and the surface of the soil, where whiteflies like to lay their eggs. Always remove dead and damaged leaves from the area as they can harbor flies and their larvae as well.
One effective method for dealing with whiteflies is the introduction of predators such as green lacewing larvae and lady bugs. These can be ordered through the mail or purchased at nurseries but always remember that multiple well-timed applications will be necessary to truly control harmful insect populations.
Also, companion plants such as Marigolds and Nasturtiums nearby can help repel whiteflies as well. My online buddy and pot pest expert MyNameStitch also recommends Permethrin dust which is safe for edible plants and can be used through early flowering if necessary.
The best way to deter and avoid infestation is to keep your growing area clean and remain ever vigilant. Any sign of pests requires immediate action and continuous monitoring. Check your plants and sticky traps daily!
Have a grow question? Ask away at deardanko@hightimes.com
Premethrins are like a synthetic Chrysanthemum, good for a wide range of pests but like all chemical controls, they have become less effective. Diatomaceous earth works well at clogging pest breathing apparatus. A light dusting should help. Remember to rinse excess dust off before harvest. Diatomaceous earth like numerous other products has been linked to some cancers.
White flies vector broad mites, which is their greatest danger.