Urban bonsai pests

Asked June 13, 2020, 2:48 PM EDT

We recently purchased an urban bonsai and within a few days it seemed to have some small notes or something on the trunk and leaves. There are small webs as well. The leaves are dropping very quickly. We do not have green thumbs but hope to save the tree.

Montgomery County Maryland

1 Response

This plant appears to have a significant infestation of spider mites. If it developed signs this quickly, it probably had the mites upon purchase and should be returned (if possible). If you do not wish to discard the plant, you can try one of the recommended treatments on this page: https://extension.umd.edu/hgic/topics/spider-mites-houseplants. Use products manufactured and labeled for houseplant/indoor insect control and not any home remedies; if you do not wish to visit a nursery to shop for them in person, you can probably mail-order them or order online for curbside pickup. Very thorough coverage of all plant surfaces (especially leaf undersides) is critical for the effectiveness of any spray. Keeping the plant in humid conditions (perhaps outside in shade during the summer, if possible) and not stressing it by allowing it to stay too wet or get too dry will help discourage future mite outbreaks. Vigilance will be key in monitoring the plant for any mite re-appearances and prompt treatment (following instructions on the product's label) will suppress recurrence.