What's happening with my Aeonium?

by Trina
(Lakeland, FL)

Hello Jackie. I have trouble in my succulent paradise again. I am getting this black speck of dust or soil like stuff on this aeonium.

At first I thought it was just dirt/soil but when it grew in number I tried the water spray and an organic 3-in-1 fungicide from Garden safe which is a fungicide-insecticide-miticide in one with 0.9% neem oil.

It worked for a couple of days but now they are back.

Now I am really getting paranoid as the lower leaves started to get yellow and fall off (don't know if this is related or it is simply going dormant with out 90F weather).

I am now see this thing (again they look like dirt or it could be just dirt) on my other succulents that were placed together in a corner where it gets morning to noon sun.

What kind of pest is it and how do I eradicate them? What makes this pest thrive? I have my greenhouse far from these containers and I am so worried that they may eventually invade my greenhouse too. Please help!

I'm thinking that the losing the lower leaves thing is normal. They do tend towards this type of growth, and the stems eventually end up a long bare stalk with the rosette on top. Behead them!

The black sooty thing is something else. I can't really tell what kind of texture this has; if it can be rubbed off, it looks like sooty mold, which is a sign that there is some kind of insect on the plant; the mold actually is harmless, but it grows on the honeydew, which is actually insect poo. Weird, huh?

What I would do is pull off the leaves that are showing this and the yellowing; be ruthless, and throw them in the garbage, and get rid of them. Wash your hands well, to make sure you don't transfer the pest (whatever it is) to healthy plants.

So for spraying, you have to continue to do this, every day for at least a few days. I might do it for a week, just to make sure you're getting all the critters. They have a trick of hatching out more when you turn your back on them.

If it's sooty mold, eliminating the pest will get rid of the mold; however, it's good to give the plants an outdoor rest if possible, where they get good air circulation and fresh air. While they're outside, you can spray them with some kind of soap spray; I recommend doing this at least a couple of times through the summer, and especially before you bring them back indoors.

Hope this helps,

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May 23, 2013
by: Trina

Some of it came of when I sprayed with water but most are stuck like glue on the leaves. Its so hard to differentiate soil vs whatever this black stuff are but you are right. A certain pest is causing it. Its actually eating thru the leaves. I might as well behead all of them since I will be mostly left with the crown once I get all the yellow and moldy leaves out. I've sprayed with water and dish soap again after reading your reply and I will spray again everyday for a week to make sure I get all of them. I think the cause of the mold could be because the container is near the pool area. Is this bad for succulents as well?

Generally, succulents prefer a dry climate, rather than high humidity. If it's too damp, then they are susceptible to fungal infections, which thrive in those kinds of conditions, especially if it's warm too. Keep me posted, fingers crossed!

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