An ongoing list of common citrus tree pests and how to eliminate them. As this is my first time growing citrus trees, I have no first hand experience dealing with these (except for fungus gnats), so Iβm keeping this here for the inevitable need and will be updating as I go.
Fungus gnats: harmless swarms will come and go and they arenβt necessarily a sign of anything bad, theyβre inevitable when thereβs excessive moisture in the soil. While theyβre not strong fliers and donβt bite, theyβre still a nuisance. You can control or eliminate them by using both sticky traps and diatomaceous earth together, along with letting soil dry out completely between waterings. I strongly suggest eliminating them when possible. Although, I have never found hydrogen peroxide solution to be effective, only a combination of sticky traps to catch adults and a significant amount of diatomaceous earth to kill the larvae.
Spider mites: these are more likely to be a problem on more mature plants, and harder to get rid of than gnats. They are extremely small, smaller than a pinhead, so youβll have to look at the leaves very closely to see them. These are best treated by gently cleaning off leaves with insecticidal soap, as well as spraying Neem oil on the leaves and soil. Diluting the Neem oil with water will help prevent any leaf burning, along with washing off the leaves with a damp towel, especially for young shoots too delicate to be exposed to natural rainfall.
Thrips:
https://www2.ipm.ucanr.edu/agriculture/citrus/Citrus-Thrips/
https://www.thegreenpinky.com/best-insecticides-thrips/
Scale:
https://www.fruitsaladtrees.com/pages/citrus-scale
https://www.reddit.com/r/Citrus/comments/14y33o4/scale_treatment/
https://www.gardeningknowhow.com/edible/fruits/citrus/controlling-citrus-scale.htm
https://www.finegardening.com/article/controlling-scales-a-common-pest-of-fruit-trees
Citrus Leafminer:
https://www.yamagamis.com/blog/how-to-treat-citrus-leafminers
https://www.agric.wa.gov.au/pest-insects/citrus-pests?nopaging=1
https://www.engalls.com.au/advice/citrus-pests-and-diseases/