Bug Identification - Ask Extension
Hello! I have some bugs destroying my Phlox but am trying to be chemical free. I'm wondering if you can give me advice on what they are and how to sto...
Knowledgebase
Bug Identification #872218
Asked June 08, 2024, 5:24 PM EDT
Hello! I have some bugs destroying my Phlox but am trying to be chemical free. I'm wondering if you can give me advice on what they are and how to stop them. Most are orange, but some are black and orange. I've tried diatomaceous earth and just a garden hose to try to spray the buggars off with little effect.
Also, I saw a spider in the garden today. I don't usually kill them, but I've never seen this kind before. Could you help me identify it?
Thank you!
-Heather
Baltimore City County Maryland
Expert Response
Hello Heather,
The insects on the Phlox look like the aptly-named Phlox Plant Bug. They look a little different from each other base don their life stage; adults have more black markings than the juveniles. Their feeding on sap in the foliage is what causes the pale stippling damage that is prominent in the photos. Despite the eyesore, they tend not to cause serious long-term damage to the plant. If you want to try suppressing them, you have a few options. Pruning back the Phlox stems to force regrowth can remove not only most of the bugs, but also (temporarily) their food source. This will, however, delay or reduce the plant's ability to flower later this summer since it will have to catch up in growth.
You could also try knocking the insects by hand into a pan/bucket of soapy water to drown them to avoid having to use an insecticide. A strong blast of plain water from a garden hose might also be enough to knock the insects off, if you keep doing it every few days, though some may make it back onto the plant, as it sounds like they might already be doing when you've tried this.
If you use an insecticide, try a low-toxicity spray like horticultural oil or insecticidal soap, but be aware that these sprays need to directly contact the pest to be effective (their dried residues have no impact), and that heavily-damaged leaves might "burn" and look worse as a result of treatment, especially during warm weather. Use labeled insecticide products, not a home remedy alternative, since they will either not work well or will risk more plant damage. If you use either of the insecticides above, repeat treatments may be needed until the Phlox Bug numbers decline. With two generations per year, you may need to monitor the plants periodically this summer for a resurgence of a new generation.
Removing Phlox plant debris in winter, where this insect's eggs overwinter, may also help to reduce populations for future years.
Diatomaceous earth can help suppress some insect pests, but more so the chewing type than sap-feeders, and regardless of that distinction, it will provide no benefit once it gets wet.
Maryland is home to hundreds of spider species, but the one pictured resembles an Orchard Orbweaver, a very common and widespread species. They don't pose a threat to people, and like other spiders, eat insects and are considered beneficial in the garden.
Miri
The insects on the Phlox look like the aptly-named Phlox Plant Bug. They look a little different from each other base don their life stage; adults have more black markings than the juveniles. Their feeding on sap in the foliage is what causes the pale stippling damage that is prominent in the photos. Despite the eyesore, they tend not to cause serious long-term damage to the plant. If you want to try suppressing them, you have a few options. Pruning back the Phlox stems to force regrowth can remove not only most of the bugs, but also (temporarily) their food source. This will, however, delay or reduce the plant's ability to flower later this summer since it will have to catch up in growth.
You could also try knocking the insects by hand into a pan/bucket of soapy water to drown them to avoid having to use an insecticide. A strong blast of plain water from a garden hose might also be enough to knock the insects off, if you keep doing it every few days, though some may make it back onto the plant, as it sounds like they might already be doing when you've tried this.
If you use an insecticide, try a low-toxicity spray like horticultural oil or insecticidal soap, but be aware that these sprays need to directly contact the pest to be effective (their dried residues have no impact), and that heavily-damaged leaves might "burn" and look worse as a result of treatment, especially during warm weather. Use labeled insecticide products, not a home remedy alternative, since they will either not work well or will risk more plant damage. If you use either of the insecticides above, repeat treatments may be needed until the Phlox Bug numbers decline. With two generations per year, you may need to monitor the plants periodically this summer for a resurgence of a new generation.
Removing Phlox plant debris in winter, where this insect's eggs overwinter, may also help to reduce populations for future years.
Diatomaceous earth can help suppress some insect pests, but more so the chewing type than sap-feeders, and regardless of that distinction, it will provide no benefit once it gets wet.
Maryland is home to hundreds of spider species, but the one pictured resembles an Orchard Orbweaver, a very common and widespread species. They don't pose a threat to people, and like other spiders, eat insects and are considered beneficial in the garden.
Miri
