Hello, I had this (dracaena?) plant happliy growing outdoors last summer in the garden and it’s been inside a south-facing window at my workplace for winter. It’s visibly weaker of course with less light and the dry air, but I just noticed what look like tiny beads of sap on the inner leaves. Looks like tiny insects are taking tiny bites? Otherwise seems to be healthy. I’m going to try insecticidal soap as that is not so toxic for an indoor environment. Just hoping to keep it growing inside for a couple more months then I can take it outdoors on a sunny day and properly spray it. Any suggestions welcome. Thanks!
Hello – Thanks for sending along the photos. Your workplace plant is indeed a dracena, probably Dracena marginata. While it’s very difficult to diagnose a plant pest from a photo, I’m going to guess that the issue you are observing is caused by spider mites. Dracena are susceptible to spider mites. Dracenas are one of the best plants for dry, indoor workplaces but these conditions are also ideal for the spider mites. The insects themselves are very small – like tiny grains of black pepper so almost impossible to see. Try holding a white sheet of paper under a leaf and gently tapping on the leaf to see if you can dislodge a few spider mites onto the paper to identify them. The spider mites feed by puncturing the leaf surface and sucking out the juices leaving a series of yellow dots on the surface. If the infestation continues, the leaf will eventually turn yellow and drop off. Spider mites are actually spiders and you may see evidence of webbing on the underside of the leaf or between the leaf and stem.
The first line of defence is a strong spray of water to knock the spider mites off the plant. As this may not be possible in your workplace and given the size of the plant, use of insecticidal soap is also recommended. Horticultural oil which smothers the spider mites can also be used. Be vigilant as you may need to spray repeatedly. Once you are again able to move the plant outside, you can try the heavy spray with water. Protect the soil while spraying so you are not just spraying the spider mites onto the soil. Once your dracena is outdoors, there will be predators such as ladybugs to help take care of the spider mites.
Good luck. Your plant looks really healthy so I’m sure it will survive this infestation with your care.
February 12, 2021