(Laguna Niguel, CA)
I have an older (about 5 years old) Echeveria succulent that is flowering like crazy and I just noticed that some of the shoots have these tiny black bugs all over them.
This plant has never had an issue before. These bugs or whatever they are seem to be stopping the growth of the flowers. The shoots where the bugs are/were most are smaller that the ones where there are less bugs and the flowers are very dry and not opening. Also, once I sprayed it with Neem it seemed like tar fell onto the leaves and I am able to rinse it off with water. Do you have any idea what these pests are?
It's dark right now so I couldn't take a picture.
Drought Smart Plants reply:
Hi Renee, it sounds as though your Echeveria has aphids.
These soft bodied insects cluster in a group on tender growth (such as the flower stalks) and suck out the juices. The black substance could be 'sundew' which they excrete. Usually, this gets mold growing on it, which is harmless to the plant, but unsightly.
The big issue is the damage from the aphids sucking apparatus, and the fact that they can carry and transmit viruses from one plant to another.
Usually, aphids can't survive either an insecticidal soap spray, or simply a sharp blast of plain water from a sprayer or garden hose, depending on the plants.
If the Echeveria is finished blooming, simply cut the flowers off, as most of the aphids will be at the top of the stalks.
Let me know if this is not what you have; in most cases, pests on succulents are temporary and most are easily dealt with by simple methods first.
See also the page on Succulent Plant Pests.
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