Mealies and flat mites and scale -- oh, my! (Updated 6/11/2022)

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Steve Johnson
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Mealies and flat mites and scale -- oh, my! (Updated 6/11/2022)

Post by Steve Johnson »

Important note: A few things have changed since I first posted this presentation on 12/30/18. The updates I make reflect my most recent information and experience -- if you've seen the presentation before, you can skip through the stuff that hasn't changed and read any sections that say "update".

Although I've dealt with these pests at various times since I built my current collection in 2011, '17 was a bad one when I got hit by all 3 in the same year. If (and more likely when) you encounter any of them, hopefully you'll be able to benefit from the experience I'm sharing with you here. This presentation is divided into 4 parts, and we'll put the first 3 under the heading of "know your enemy". The 4th part will discuss remedies.

Before we continue, I just wanted to thank CactiGuide for letting me use photos from the website's Cacti Pests & Diseases page. Thanks also to Harald (one of our "veteran" forum members) for his significant contributions to that page.

Part 1 -- scale insects

Mealybugs are a type of scale, and they're the most common cactus pest. I'm no stranger to mealies -- in fact, they were the bane of my young existence shortly after I started my first collection in 1970. What I didn't know then is that mealies can attack all parts of the plant, including the roots. I sure know it now, so first, we'll examine the ones we can obviously see. The above-ground kind attacking the stem...

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and yes, even the spines:

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Believe it or not, the primary culprit is the citrus mealybug Planococcus citri. If you'd like to get an in-depth look at this enemy, you'll find a good article on it at Wikipedia here.

Below-ground mealies are more insidious because they do their nasty work hidden from plain sight:

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Root mealies were never a problem until I unpotted a Discocactus buenekeri to "prune" excess pups in early March 2017, so I was somewhat horrified to see a full-blown infestation. This prompted me to do some research, and the following quote from Cactus Nursery in the UK should be instructive:

"Root mealybugs (Rhizoecus falcifer) are among the worst pests of cacti and other succulents. They live almost exclusively on roots and the parts of the stem that are below the surface. They are similar to stem and spine mealybugs in that they also secrete whitish, woolly, or powdery wax. Root mealybugs prefer dry substrates. They multiply particularly rapidly during the dry winter dormancy period. Affected plants look pale, become sickly, and gradually die. Plants damaged and weakened by root mealybugs are especially susceptible to fungal diseases."

I was hoping the infestation would be localized only to the Discocactus, which I took care of in the appropriate manner. But when I repotted an Eriosyce senilis at the end of that May, there were -- root mealies. Uh oh. When I finally realized that they may have spread to other pots too, I noticed a number of cacti showing signs of illness which can be caused only by root mealy infestation. Here are a couple of examples from my collection. Exhibit A, Gymnocalycium baldianum on 5/22 and 6/13/17:

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After regular springtime waterings, the Gymnocalycium should've been plumper. However, the roots weren't taking up enough water, and the skin color didn't look healthy at all.

Exhibit B -- Parodia subterranea on 3/25 and 6/18/17:

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Once again, regular springtime waterings should've led to a plump and happily growing Parodia. Instead, the plant was going in the opposite direction, and its buds were aborting. 2 weeks after I repotted the Eriosyce, I was able to apply the remedy that got the entire collection on track for a mealy-free summer, so I'll show you a much nicer before-and-after view of these cacti in Part 4.

The other type of scale insect we'll commonly encounter is armored scale. Like mealies, A. they'll suck the juices out of our cacti, and B. infestations need to be knocked down before they go out of control and eventually kill the plant. From CactiGuide, this Astrophytum may be a goner:

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Armored scale up close and personal:

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Unlike mealies, this pest is selective about what it'll attack, although why armored scale goes after only some species is something of a mystery. Could it be that they can't latch onto thick-skinned cacti? Not necessarily -- Coryphantha retusa and Obregonia denegrii have thick waxy skins, but it wasn't enough to protect mine from being infested. I got the Coryphantha in July 2013, and my first run-in with these little nasties took place when they had fun at the plant's expense the following June:

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Once I dealt with them, they never came back. When I received the Obregonia from an eBay seller in May 2016, it already had a low-level infestation:

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After I knocked it down, the plant got infested again in 2017. Applying the (usually) effective treatment one more time should've done it, but the scale came back yet again the following year. While the Coryphantha bounced back from its one and only scale attack, it's possible that the seller sent me an Obregonia that wasn't healthy enough to prevent repeated assaults. I finally gave up and threw the thing away, so I'll simply chalk up the loss to bad luck. Anyway, since we know that armored scale can go after thick-skinned cacti, here's a follow-up question...

Maybe they won't find certain species tasty enough? Doesn't keep them from doing a "taste test", which I came to find out when they "tasted" my Astrophytum asterias, Melocactus matanzanus, and one of my Turbinicarpus polaskiis in 2018. While the insects didn't decide to go for an infestation, all it took was a few for the plants to be sickened just enough to be noticeable. The experience told me that if you see even a hint of armored scale on your plants, you should take remedial action right away.

A less comonly encountered type of scale insect is Cochineal:

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As stated by CactiGuide's Pests & Diseases page, Cochineal insects confine themselves to Opuntia and Nopalea species, including Cylindropuntia. And the good news is that they won't kill the host plant.

Part 2 -- pest mites

Red spider mites are absolutely the worst because they're very aggressive in terms of infestation and reproduction. Although barely detectable with the unaided eye, the tiny webs they spin all over your plants are a telltale sign that you have them. A magnifier helps, so if you have one, here's what they look like:

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Examples of the damage red spider mite infestations leave behind:

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Red spider mites thrive in dry conditions, so if your climate tends to be humid, you won't see them. Shouldn't have a problem with mites then, huh? Unfortunately no, and this brings us to what is perhaps the least-understood cactus pest:

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That's the flat mite Brevipalpus phoenicis, and you'll find an informative article on it at Wikipedia here. A quote from the article will tell you if flat mites could be a problem: "Ideal conditions for this species are a temperature range of 25–30 °C (77–86 °F) with high relative humidity." The Mediterranean coastal microclimate in my part of Los Angeles is humid enough for it, so thanks to Wikipedia, here's what I've learned about flat mites:

Adults grow to a length of 280 microns (0.011 in), which makes them impossible to detect without magnification. No telltale webs either, and I call them "drive by" pests because they'll come and go, leaving their damage behind before you know they were even there. From my collection, here's a Sulcorebutia rauschii with flat mites caught in the act (top) and an example of what their damage looks like (bottom):

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2 more examples -- Gymnocactus ysabellae...

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...and Eryosice odieri:

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2017 was the year to see flat mites visiting my Coryphantha hesteri -- after the "drive bys":

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Compared to red spider mites, flat mites aren't nearly as aggressive, and their reproductive cycles are slower. Another difference is that they tend to go after the base, although they can sometimes attack tender new growth as well. Hot days in winter (and I have more than a few of those) may encourage them enough to get active when cacti are dormant. For example, I took the Sulco rauschii photos I just showed you in early February 2014.

Chances are that you're hearing about flat mites for the first time here. Since you now know what their damage looks like (and your climate fits the profile), you'll be able to tell if you could have a flat mite problem. If you at least suspect that you do, a 10x magnifier will be helpful for confirmation. While catching them in the act can be tricky, regular plant inspections with a magnifier are highly recommended -- this applies to flat mites and red spider mites.

Part 3 -- vectors

A simple, yet fancy word for describing how we get pests to begin with. The most obvious vector is bringing uninvited "guests" home with you. The best cactus and succulent nurseries go to great lengths to maintain their reputations by selling only high quality pest-free plants. If that's what you're doing, then no worries, especially when you're getting bare-root cacti. If you're buying from private collectors of unknown reputation -- well, that could be problematic (it's how I ended up with a scale-infested Obregonia). General-purpose nurseries and "big box" garden centers certainly aren't the best because they know little or nothing about caring for the cacti they sell. Not to say that you should never buy plants from these places, but you'll need to inspect your cacti and/or succulents as closely as possible before you decide to make the purchase. Even then, there's no 100% guarantee that you're introducing pest-free plants to your collection, so your first order of business should be to immediately unpot and inspect them from top to bottom. If you see anything nasty, quarantine the affected plants so their tiny "hitchhikers" don't spread to the rest of your collection.

There's a vector that won't be obvious to inexperienced growers, and it has to do with the fact that 5 of the 6 pests we're discussing aren't specific to cacti. Neighborhood plant life may be the source of your ongoing pest problems, although the list of possible non-cactus hosts is way beyond the scope of this presentation. Bottom line is -- if you grow cacti, you'll be dealing with pests in one form or another. Regardless of how you got them, knowing your enemy is half the battle. This takes us to the other half...

Part 4 - remedies

Pest problems have short-term and long-term solutions, so I'll break it down by category.
  • Short-term solutions
Scale insects -- mealies, armored scale, and cochineal have built-in protections that make insecticide sprays useless. Stem and spine mealies cling to the plant, so the only way to physically remove them is with tweezers. Armored scale and cochineal insects can be knocked off with tweezers or a high-pressure nozzle blast from your garden hose. Unfortunately, physical removal won't take care of any eggs left behind, so be prepared to deal with new generations of these pests. (People who are able to use the long-term solution will be happier!) If you have root mealies, soak the roots in warm, soapy water, then rinse them thoroughly, let them dry out, and repot the plant. While insecticidal soap is great, plain dish soap will do the job too. This treatment kills the root mealies and their eggs, which is the one advantage you have over the above-ground nasties.

Pest mites -- Isopropyl alcohol (IPA) is the one miticide easily found worldwide because it's available at grocery stores and pharmacies. Used as a contact spray, IPA will kill mites instantly, although complete coverage is required so you don't have them hanging around on dry spots. There are a couple of drawbacks with IPA -- first, it can ruin the waxy skin of some cactus species, so be careful about that. And second, contact sprays kill adult mites, but it won't kill their eggs. As with scale insects, you'll be chasing after subsequent generations of mites. (It's what makes red spider mites such a pain, although flat mites are somewhat easier to deal with given their slower reproductive cycles.) So your plants don't develop a phototoxic reaction, spraying should be done away from direct sunlight, or better yet -- at night.
  • Long-term solution for all types of scale insect
The most effective treatment is an Imidacloprid soil soak, because the Imidacloprid is taken up by the roots through systemic action that makes the plant's juices toxic to these pests. Takes awhile to kick in, so if you have an infestation already in progress, give it a few weeks before you start to see the infestation clearing up. If you're dealing with a root mealy problem systemically, the improvement may not seem so readily apparent. But it will be, so let's go back and look at the Gymno baldianum and Parodia subterranea I showed you in Part 1. Taking the "afters" and turning them into "befores", here's the Gymno on 6/12 and 10/8/17...

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...followed by the Parodia on 6/18 and 9/23:

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That Imidacloprid really did wonders, didn't it? :D

Soil soaks have to be done when cacti are active in the growing season, and spring is the best time if you'd like to do this as a preventative measure. Some people tend to take a more cautious approach, reaching for the Imidacloprid only if they detect signs of a scale problem. I used to be one of those people before I saw what happened in 2017 and '18. Long story short, I discovered that ants from a nearby Bougainvillea bush were responsible for the stem and root mealies infesting some of my cacti in 2017. Then when the armored scale came back the following year, I said "enough is enough" -- implemented in spring 2019, the entire collection has been getting a preventative soil soak every year. This makes sense because I know that the mealies and armored scale are coming from sources beyond my control. If you find yourself in a similar situation, annual prevention is a good idea. If you don't have a problem with scale insects that keep coming back every year, you can take the more cautious approach with soil soaks only on an as-needed basis.
  • Important note: Contrary to what you may have heard or read elsewhere, Imidacloprid protection with soil soaks has an expiration date of about 3 months. If you do a soil soak in April or May and you see mealies/armored scale showing up in July or August, give the affected plant(s) another soil soak.
My product of choice used to be Bayer Advanced 3-in-1 containing 0.47% Imidacloprid. After Bayer Advanced became BioAdvanced, Imidacloprid was dropped from their formulation (how they still called their product "3-in-1" is beyond me). BioAdvanced put it back in, although when my bottle under the old Bayer name was about to run out, I decided to go with something better -- Bonide's Annual Tree & Shrub Insect Control liquid concentrate available through Amazon here:

https://www.amazon.com/Bonide-037321006 ... 220&sr=8-7

The Bonide product contains 1.47% Imidacloprid, dilute 1/4 cup per gallon of water or 1 tbsp. per quart for growers who have only a few plants they need to soak. Just be aware of the fact that the concentrate doesn't dissolve quickly, so here's a "how to":
  • When you pour the concentrate into your container of water, make sure you have the its cap on tight (but not too tight!), and shake like the dickens. After a couple of minutes, take off the cap and see if the Bonide is thoroughly dissolved. If it's not, put the cap back on, and shake like the dickens again, then take off the cap to see if it's thoroughly dissolved. If it's still not fully diluted, either go through the process again or let the container sit for an hour, and give it a final shake-shake-shake. The point is to make sure that you don't have clots of Bonide concentrate floating around in the water when you apply your soak.
The bicarbonates in hard tap/well water will interfere with Imidacloprid uptake through the roots, so it's best to do soil soaks with rainwater or distilled water whenever possible. If you're using another Imidacloprid product, be sure that you pay attention to the percentage on the label, and adjust the amount for dilution if required. (Adding in liquid fertilizer is optional, but a good idea for those of us who use it.) NEVER dump Imidacloprid-laced water down the drain or spread it around your garden soil -- capture the runoff and dispose of it through your local home hazardous waste center.

6/11/2022 update

I've been using Imidacloprid for 11 years, and I realized that I very well could end up with Imidacloprid-resistant pests. The problem was trying to find something we can rotate it with, and a systemic product that isn't a neonicotinoid. Thanks to a recent recommendation Craig Fry posted in this thread, we found a good one -- Cyzmic CS, available on Amazon:

https://www.amazon.com/CSI-Cyzmic-Contr ... 192&sr=8-2

Dilution is 12 ml (2.5 tsp.) per gallon of water. Luckily, I'm not seeing any telltale signs of mealies or armored scale, but if I do, it'll be Cyzmic.
  • Long-term solution for pest mites
It would be nice if we didn't have to rely on sprays that kill mites only on contact. Chasing after mite infestations is no fun at all, especially since it's difficult to keep up on the spraying routine as you try to knock down one generation after another (and another and another). Thankfully we have an excellent alternative in the form of translaminar (AKA transdermal) sprays. When we use a translaminar spray, the miticide gets into the plant's skin for an almost-systemic action that lasts up to 30 days. These translaminars break the mites' life cycle, and they're a pretty major advantage over contact sprays.

My miticide of choice is TetraSan, and it's in granular form -- dilute 1/2 teaspoon in a gallon of water. I recently discovered another translaminar miticide I can use to rotate with TetraSan, and the active ingredient is Abamectin sold under the Avid brand name. It comes in liquid form -- dilute 1/4 tsp. in a gallon of water. Avid and TetraSan have an upside and a downside. The downside is that both products are really expensive. But a little bit goes a long way, so for those of us with relatively small collections, the upside is that we can do one-stop shopping with Avid and TetraSan being sold in small quantities through The Flytrap Store. (Oddly enough, carnivorous plant growers have the same mite problems we have!) To get the best translaminar effect, spray your cacti at night when their stomata are open so that the miticide penetrates the skin's outer layer. Important note regarding Avid: Unlike TetraSan (which is a "spray once" application), you'll need to apply Avid by spraying on day 1, spraying 3 days later, then spraying again 3 days after that.

I have zero experience with red spider mites, so I don't know if preventative measures are warranted. Since you can actually see them (or at least their telltale webs), that would be the time to go for the TetraSan or Avid spray. If they come back, you'll be prepared for them as you rotate miticides. My personal experience is confined to dealing with flat mites, so the problem I have to consider stems from the fact that I won't know if they're there or not. Such being the case, I decided to make 2018 the year for beginning a regular preventative treatment schedule, rotating between TetraSan and Avid every month or so in the spring and summer. They seem to give up the fight rather easily, so I'm not too concerned about the possibility of seeing resistant flat mites over the long haul.

Thoughts, anyone?

This thread is wide open for discussion, so please feel free to post comments, suggestions, tips, etc. And there are a few things that would be especially helpful...
  • Products we can add to the anti-pest toolkit
Although I don't know if they even exist, a systemic miticide would be great. If not, another translaminar miticide to go with TetraSan and Avid at least gives us another tool in the kit. For those of you with any suggestion here, please be sure to:

A. Specify the product's brand name and what it does.
B. Tell us if the product is currently available to hobbyists. Environmental regulations vary from state to state, but unless the product is sold only to professionals, hobbyist growers can determine whether or not they'll be able to buy it in their state.
C. Let us know about where we can find the product online if it's not something obvious (like Amazon or eBay).
  • If you live outside the US
Environmental regs may be a barrier that'll prevent you from buying the products we're discussing. If you have alternative treatments that'll be helpful to other non-US growers, we'd love to hear from you.

Okay, folks -- let's go after those pests!
Last edited by Steve Johnson on Tue Jan 01, 2019 5:06 am, edited 1 time in total.
If you just want photos without all the blather, please visit my Flickr gallery.
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ElieEstephane
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Re: Mealies and flat mites and scale -- oh, my!

Post by ElieEstephane »

Hello steve
This is a very helpful topic! I will make it sticky so it stays on top.

Personally, i'm like you an advoacte of preventative soaks. Last year i used acetamiprid as a systemic insecticde. It worked fantastically! I saw progress within literally one week. It comes as a powder which you dissolve in water. The resulting solution is lyophobic (doesn't have an affinity to wet waxy substances ie it will not directly contact the pests). So i add a little soap to disperse the acetamiprid on the skin of the pests since it can also act as a contact insecticide.

Im am not sure about its legal status in the US bs it's on the way to be banned in the EU. That's why i'm gonna stock it and also look around for Imidacloprid
There are more cacti in heaven and earth, Horatio, than are dreamt of in your philosophy.
One of the few cactus lovers in Lebanon (zone 11a) :mrgreen:
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Steve Johnson
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Re: Mealies and flat mites and scale -- oh, my!

Post by Steve Johnson »

ElieEstephane wrote: Mon Dec 31, 2018 9:13 am Hello steve
This is a very helpful topic! I will make it sticky so it stays on top.
Thanks so much, Elie! I was hoping that my presentation might rate a sticky, so I'm pleased to see it's up there. And your tip is exactly the kind of thing we could use as we have an opportunity to expand the pest knowledge base here. By the way...

If Lebanon hasn't banned neonicotinoids (yet), look for Imidacloprid under the Provado Ultimate Bug Killer brand name. In case you can't find a local source, Amazon UK may be your best bet:

https://www.amazon.co.uk/SBM-Life-Scien ... ds=provado

Best wishes for a happy, healthy New Year, my friend!
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ElieEstephane
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Re: Mealies and flat mites and scale -- oh, my!

Post by ElieEstephane »

Yes looking for imidacloprid is on the top of my list above actually building a greenhouse because i have only eradicated 99% of the root mealies and they will come back through winter i'm sure.
One thing i like to add though is since i use a very free draining mix, i soak my potted plants for 20-30 minutes at night after at least a month into the growing season to make sure they have had a good drink.
There are more cacti in heaven and earth, Horatio, than are dreamt of in your philosophy.
One of the few cactus lovers in Lebanon (zone 11a) :mrgreen:
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nachtkrabb
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Re: Mealies and flat mites and scale -- oh, my!

Post by nachtkrabb »

Hi Steve, what a mess... I do feel with you and your plants. Good luck to you!

To get rid of insects and spiders overground I suggest to spray the plants dripping wet with pure methylated spirit. It doesn't hurt the plants, but the insects incl. mealy bugs are suffocated. Only scale insects seem to survive sometimes. You have to repeat the proceedings three or four times with 5 to 7 days intervall to catch the newly hatched ones.
Yes, do look at the roots, too, in strong cases: Get off all the soil and bath them for a very short time (some secs are enough) in methylated spirit. Mine survived without the pests. Let them rest some days before repotting to repeat the process at least twice with 5 to 7 days intervall.
For plants in pots: Please don't forget to check the outside and especially the bottom of the pots, also the saucers (if any) and the place below. Below the saucers I sometimes catch mealy bugs and wipe them away with -- what else -- methylated spirit.

I swear on methylated spirit as it works very well, is cheap, easy to get, and it is environmentally friendly. Plus it is easy to use, I use a normal spray bottle as for ironing.

I always hate winter as then the mealybugs return and we have to "refight" them again. During summer, outside on the balcony, they are invisible. No, I don't even find them on repotting. It is a miracle.

ElieEstephane, I join in: Good idea from you to make this sticky.
N.
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Steve Johnson
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Re: Mealies and flat mites and scale -- oh, my!

Post by Steve Johnson »

Thanks, nachtkrabb! It's good to know that methylated spirit is effective at killing mealies. If my Imidacloprid soil soaks lead to pest-resistant mealies in the future, I'll know exactly what to do!
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Re: Mealies and flat mites and scale -- oh, my!

Post by dinfelu »

steve

I have read it from beginning to end, it is very interesting, and now it is born in me to review
in detail each one of my cactus

regards
🌵 Gabriel
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Pesticide shelf life

Post by Steve Johnson »

Spring is almost here, so for those of us who need to use pesticides, now is a good time to remind you that your products of choice have a limited shelf life. If and when you find it necessary to use them, please be sure to do the following:
  • Whenever you buy pesticides, label the product(s) with an expiration date. In the absence of specific manufacturer shelf life info, figure on 2 years. The active ingredients may lose their effectiveness after that.
  • Once the pesticides have passed their expiration date, you'll need to replace the old stuff with new stuff. Dispose of expired pesticides responsibly by taking them to a home hazardous waste center.
This applies to products like Bayer 3-in-1, Avid, TetraSan, etc. Alcohol and soap don't have a shelf life, so if you want and/or need to use them as alternative remedies, you won't have to worry about it.
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CephaloSquad
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Re: Mealies and flat mites and scale -- oh, my!

Post by CephaloSquad »

Hi, I'm new and just found your post. I've dealt with aphids and mealy bugs so far. This has been a really educational and helpful read, thanks for writing it. the image guides are particularly useful. For the chemicals you mentioned for preventative soaks- can you use multiple together? Since my succulents are in growing season right now I want to do a preventative soak against bugs and mites too!
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Steve Johnson
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Re: Mealies and flat mites and scale -- oh, my!

Post by Steve Johnson »

CephaloSquad wrote: Thu Apr 25, 2019 5:03 pm Hi, I'm new and just found your post. I've dealt with aphids and mealy bugs so far. This has been a really educational and helpful read, thanks for writing it. the image guides are particularly useful.
You're most welcome! I'm glad that people are getting some use out of my presentation, and it was nice to cover all the details in a comprehensive manner.
CephaloSquad wrote: Thu Apr 25, 2019 5:03 pm Since my succulents are in growing season right now I want to do a preventative soak against bugs and mites too!
I've been searching high and low for a systemic miticide -- apparently (and unfortunately) they don't exist, although translaminar miticide sprays work well together with Imidacloprid soil soaks as a "1-2 punch" against mealies, armored scale, and pest mites. My preventative approach is as follows:

Imidacloprid (that's your systemic) -- a soil soak for all plants in the spring (I'll be doing it for most of my cacti this weekend). Do it once, and you'll be set for the rest of the growing season. As I said in my presentation, this is highly effective on all types of scale insect, mealies included.

Translaminar miticides -- oddly enough, Imidacloprid is known to encourage mite activity. It takes about 2 weeks for the full systemic effect to kick in, so if you're doing a soil soak, apply translaminar spray a week or two later. Given my experience with flat mites, I've found that monthly preventative translaminar treatments work best since I don't know if they're there or not. I sprayed my mite-prone cacti with TetraSan toward the beginning of April, so I'll spray them again with Avid in about a week. Then it'll be TetraSan in June and August, rotating with Avid in July and September. Unlike flat mites, red spider mites can be detected without a magnifier -- if that's the type of pest mite you're dealing with, you may not need regular preventative treatments beyond spraying right after an Imidacloprid soil soak. If you see the nasty little things coming back, you can knock them down again with the translaminar spray.
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Scrap
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Re: Mealies and flat mites and scale -- oh, my!

Post by Scrap »

nachtkrabb wrote: Sat Jan 05, 2019 10:46 pm Hi Steve, what a mess... I do feel with you and your plants. Good luck to you!

To get rid of insects and spiders overground I suggest to spray the plants dripping wet with pure methylated spirit. It doesn't hurt the plants, but the insects incl. mealy bugs are suffocated. Only scale insects seem to survive sometimes. You have to repeat the proceedings three or four times with 5 to 7 days intervall to catch the newly hatched ones.
Yes, do look at the roots, too, in strong cases: Get off all the soil and bath them for a very short time (some secs are enough) in methylated spirit. Mine survived without the pests. Let them rest some days before repotting to repeat the process at least twice with 5 to 7 days intervall.
For plants in pots: Please don't forget to check the outside and especially the bottom of the pots, also the saucers (if any) and the place below. Below the saucers I sometimes catch mealy bugs and wipe them away with -- what else -- methylated spirit.

I swear on methylated spirit as it works very well, is cheap, easy to get, and it is environmentally friendly. Plus it is easy to use, I use a normal spray bottle as for ironing.

I always hate winter as then the mealybugs return and we have to "refight" them again. During summer, outside on the balcony, they are invisible. No, I don't even find them on repotting. It is a miracle.

ElieEstephane, I join in: Good idea from you to make this sticky.
N.
Hi Nachtkrabb, I am currently fighting spider mites and im interested in your experience with spirits on species like copiapoa and astrophytum - is there no damage to the wool? Thanks in advance! /Malin
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nachtkrabb
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Re: Mealies and flat mites and scale -- oh, my!

Post by nachtkrabb »

Oh sorry, Scrap, I just realized your question *NOW*. :-(

Well, I have used methylated spirits on Astrophytum with very good results plus no problems. I never had a Copiapoa, so no idea.

I do hope by now your plants are healthy and "spider mite-free"?
N.
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RichR
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Re: Mealies and flat mites and scale -- oh, my!

Post by RichR »

By methylated spirits, do you mean denatured alcohol? I have used isopropyl alcohol for mites before, but I hadn't heard of using methylated spirits. I made the mistake of spraying some echinopsis with isopropyl alcohol once while they were out in the sunlight. They were horribly burned and unsalvageable.
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Steve Johnson
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Re: Mealies and flat mites and scale -- oh, my!

Post by Steve Johnson »

RichR wrote: Sun Jun 09, 2019 11:48 pm By methylated spirits, do you mean denatured alcohol? I have used isopropyl alcohol for mites before, but I hadn't heard of using methylated spirits. I made the mistake of spraying some echinopsis with isopropyl alcohol once while they were out in the sunlight. They were horribly burned and unsalvageable.
Methylated spirits = denatured alcohol. Alcohol is alcohol, so it doesn't matter which kind we use. As I said in my presentation, spraying should be done away from direct sunlight, or better yet -- at night.
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Re: Mealies and flat mites and scale -- oh, my!

Post by mikethecactusguy »

I have been smoking cigars for 25 years. I used to flick the ash's into our flower pots around the back yard. I never realized until reading this article how beneficial it is to the plants. Imidacloprid
Who would have thunk-it.
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