Is this a disease or is it normal?

Trouble shoot problems you are having with your cactus.
plantasia
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Re: Is this a disease or is it normal?

Post by plantasia »

I am really anxious about how to treat it now.
I have a lot of other plants and usually I am very diligent about cleaning the leaves with Marseille soap mixed with water. I guess what really works is my frequent and mechanical wiping of the leaves but it's effective and no harm is caused to the plant.
With other treatments however I can't say the same thing sadly.
The only exception it been treating some plants with a nettle oil spray solution brought to the store. It worked perfectly also on the roses.
But for example I tried to save a rhipsalis from mealybugs by sprying a product specific for mealybugs and the poor thing just died.
And now my beautiful kalanchoe is dying for a fungus in front of my eyes and it's painful. I tried rubbing alcohol and first it didn't work at all and after it was too much.
If the Monvillea didn't have the spines I could treat it like the other plants, wiping it frequently. But it's huge and so difficult to handle as it has sooo many spines. I should spry it with something but I don't know what. Q-tip and rubbing alcohol might not be enough I guess.

Anyway today I repot it. I wanted to see if it had root mealybugs and just to give it better soil because I know that my boyfriend's grandma isn't very meticulous and she has a lot of infested plants. I found some mealybugs in the soil. Nothing big, just very few of them. You can barely notice them. I cleaned carefully the roots and repot it in fresh soil for cacti. I did not treat the roots with chemicals or anything else as I know roots are delicate and I didn't want to mess it up. I just hope it will be fine.

I have neem oil at home but I never really used it on plants (except a tiny bit in the soil in order to kill fungus gnats which didn't really work). I read some many different stuff that it's really difficult to trust it.
The difficulty is higher because the international community is more active but most of the times in my country I can't find the products that are advised.
Minnesota
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Re: Is this a disease or is it normal?

Post by Minnesota »

Plantasia--there's a man on this site that's brilliant with these issues. He posted on your topic earlier. His name is Steve Johnson. If he doesn't see this most recent post, email him. Translating his knowledge to your problem and applying it is my best suggestion.

Isolation of the infected plant(s) and continued mechanical removal/cleaning is a low-tech maintenance. Be careful with Neem oil--am reading cautionary tales. Also, be careful of too much alcohol.

Approach Steve; I trust his experience and knowledge.
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Steve Johnson
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Re: Is this a disease or is it normal?

Post by Steve Johnson »

Minnesota wrote: Fri Jan 13, 2023 2:38 am Plantasia--there's a man on this site that's brilliant with these issues. He posted on your topic earlier. His name is Steve Johnson. If he doesn't see this most recent post, email him. Translating his knowledge to your problem and applying it is my best suggestion.

Isolation of the infected plant(s) and continued mechanical removal/cleaning is a low-tech maintenance. Be careful with Neem oil--am reading cautionary tales. Also, be careful of too much alcohol.

Approach Steve; I trust his experience and knowledge.
Well, Minnesota, I'm flattered! :D

Call this presentation "everything you wanted to know about cactus pests but were afraid to ask":

viewtopic.php?t=42129

Plantasia -- unfortunately for you, Italy has banned neonicotinoids (including Imidacloprid), so you won't be able to get the only type of systemic insecticide that offers the long-term solution I discuss in my presentation. However, you do have other options. This is from the Iowa State University Horticulture and Home Pest News website:

"Insecticide sprays are available for mealybugs and other houseplant pests. Use aerosol or hand pump spray products made just for houseplants. These may contain any of several different ingredients, including insecticidal soaps, pyrethrin, neem, or a synthetic pyrethroid such as permethrin, bifenthrin or resmethrin. Granular insecticides that you add to the soil of infested houseplants may be effective. Use with caution and read and follow all label directions."

The more I think about it, the more I'd be inclined to stay away from Neem oil. On the other hand, pyrethroids seem to be quite effective against mealies, and you can find a pyrethroid product on Amazon Italy:

https://www.amazon.it/PROTECT-GARDEN-IN ... 93&sr=8-14

Fungal infections are a much tougher problem, and I don't know of any fungicides that are effective on cacti and succulents. The best (perhaps only) thing to do is stop them before they have a chance to start. Poor ventilation is one source of fungal problems, although I don't know if you can do anything about that in your home. Another source -- soils that are rich in organic material. The best soil going into cactus and succulent mixes is one with a bare minimum of organic stuff, and IMO commercial potting soils are the worst. If there are any nurseries in your area, find out if any of them sell sandy loam soil that isn't composted -- that would be ideal.

And finally, you may want to contact cactus and succulent clubs in Italy for advice on what you can do to improve your growing situation. Here are a few links for you:

https://digilander.libero.it/aers/

https://www.cactus.it/index.php?option= ... Itemid=111

https://www.cactus.it/index.php?option= ... &Itemid=65

I checked, and these links are active, although I don't know if they'll point you to anything helpful. Worth a shot, anyway.
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ohugal
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Re: Is this a disease or is it normal?

Post by ohugal »

The above comments are helpful. Neemoil can have adverse effects on the waxy layer of cacti and succulents, but it depends on the percentage. Unfortunately for mealybugs you definitely need a higher percentage than for preventive use. If you use it, keep it out of direct sunlight as suggested above. Also, repeated treatments are in order. The interval depends on the enviromental conditions, but is about 7-10 days.
Isopropylalcochol I have used without much problems, but I've never used it solely to get rid of them. Rather I use it as an inbetween solution when I don't have time because of work, etc... I always keep a spray bottle with IPA on the ready. Also here, be carefull with exposure to sunlight when applying.
A systemic insecticide, if you have access to it, is an effective solution. The plant does need to be actively growing though when watering it with the insecticide solution. I don't how it works when spraying with a systemic insectide. Please take precautions when using such products.
For sure, isolate the plant from the rest of your collection until the problem is solved.
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FredBW
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Re: Is this a disease or is it normal?

Post by FredBW »

Don't kill it with kindness. This is probably the worst time of year to have problems. The goal right now is to keep it as healthy as you can till spring.
It is a really bad time of year to repot. But you found mealies,so it no doubt needed it. But now you have to resist temptation to water it and "mess with it". It shouldn't be watered for at least a week in normal growing season to let the roots recover. In January the time is at least double. If you have already watered it,it might not hurt to put it in dry soil depending on how much you watered it. If it were mine i would probably give it a couple shot glasses of water in a couple weeks (others will probably tell you different :) ) But it sure doesn't need to be wet.
But I think after repoting ,it's best to leave it be so it can recover. Touching up any mealies you might see with a q tip.
I don't think i would use any neem oil either for a while after repotting it.
plantasia
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Re: Is this a disease or is it normal?

Post by plantasia »

Sorry for not writing a replay earlier.

Thanks Minnesota for suggesting Steve Johnson and thank you Steve Johnson for writing such articulate and clear advice.
I read your guide and it's fantastic, really well made.
I keep my plant collection inside in the winter time and since I live in a small open space flat that means that they are in the zone in which I eat, work and relax. My partner, which also works from home, is absolutely adamant about not spay anything toxic on the plants. I could do it outside but he still doesn't want to because later I have to bring the plants inside. A guy (which is the expert in pests in the shop in which we usually go) told him that he is actually right in being concerned about it.
He seems more open about watering with a systemic product but I am actually the one that chickens out about this because I have never done it and I am afraid to kill the plant. When I spray something I can do a little test on a small portion and keep an attentive eye on the consequences of my patch test. But I do not have that kind of control over a systemic pesticide so I am like very afraid to try even if I think it might be the best solution as I have a lot of plants now and it's very difficult to keep pests under control since I don't have a natural environment aka natural predators around.
In response to FredBW, I know it wasn't the best thing to do to repot in this time of the year but someone suggested that I might have some root mealybugs and I just got this feeling that I had them. And indeed I found them in the terrain even if it was still a very tiny spot. I didn't treat the roots properly like written in Steve Johnson's guide. I just freed the roots from the old soil, cleaned properly the pot and repotted it with fresh soil. I think it might not be enough as I might have not killed the eggs. But I was too concerned about doing something else. Steve suggest dish soap but wouldn't that be too aggressive for the roots? I really don't know. I didn't water the first three days after changing the soil but then I decided to give it just a tiny tiny sip of water because it felt like it was struggling in grabbing the terrain (It's a huge plant).
And yes, ohugal, I am not convinced at all about neem oil.

Right now I am doing as it fallows: me and my boyfriend work from home and so we keep the plant near us during the day and we take turns in observing the plant that we keep on the desk near our computers. We are using Isopropyl alcohol 70%, q-tips and a magnified lens. Little by little we are pocking when we see those darn devils coming out from their hiding spots. I have no idea if this is enough but it's still in its early stage and we can find no more than 15ish every day (and like I said, it a huge plant). I really hope this will suffice for now.

In regards of the fungus I had in my kalanchoe, it sadly died terribly. I treated it with Isopropyl alcohol by spry a solution of 1 part of Isopropyl alcohol and 9 parts of water. It felt right as I was afraid that only Isopropyl alcohol, even if at 70%, would really hurt the plant. I did this treatment once a week for one month. It did not work at all. So in a desperate attempt I spread the 70% Isopropyl alcohol on the few leaves that were left. It did a sort of damage, it wrinkled the leaves terribly leaving the plant with an unhealthy aspect.
It still didn't look ok.
My brother stopped by and gave me some suggestions. I decided to follow his suggestions because he gave me the kalanchoe as birthday presents, he is an expert in fungus and studied something related to botanical studies. He suggested to repot the plant in fresh soil and to spry backing soda. In his opinion fungus hate basic PH so this would kill the fungus. Well what it did instead was to accelerate wildly the fungus. The day after the plant was completely covered, completely black and very much dead.
So yeah don't do that. My poor kalanchoe.
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Steve Johnson
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Re: Is this a disease or is it normal?

Post by Steve Johnson »

plantasia wrote: Wed Jan 18, 2023 1:47 amSteve suggest dish soap but wouldn't that be too aggressive for the roots?
Not with a 2% soap solution. Plain dish soap is fine, but insecticidal soap would be better. Don't rinse the roots afterwards -- when they dry out, soap residue will give you some extra protection once you repot.
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ohugal
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Re: Is this a disease or is it normal?

Post by ohugal »

You could try to unpot the plant again and thoroughly clean the root system. Soak the the plant in an insecticide solution, let it dry and pot it up again. You probably should refrain from watering until the growing season. I understand the scepsis towards toxic products, so perhaps Steve's dish soap is an alternative solution. There is also the hot bath method discussed here: https://cactiguide.com/forum/viewtopic.php?t=41817.
You could also continue with the IPA spot treatment until growing season and then go back at it with a more thorough approach.
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plantasia
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Re: Is this a disease or is it normal?

Post by plantasia »

By plain dish soap do you mean every kind of dish soap?
I am asking because of the different market among countries (for instance the Isopropyl Alcohol is nearly impossible to find in Italy while it seems grocery-store-common in US as I seen it suggested everywhere).
Here we use Marseille soap for basically anything like it has some sort of holy grail so I was wondering if maybe that is ok also for the roots (I already use it successfully for wiping my plant's foliage).

I don't know about repotting again ohugal. I am keeping a hyper close eye on the plant during the whole day and I will do it until I don't see any signs of mealybugs for more than a week. If everything goes ok I will repot it as springtime arrives and I will then clean properly the roots. I am done giving it water for the winter. It was just a tiny tiny sip in the new soil.
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