mealy bugs

Mableton, GA(Zone 7b)

I got 'em. I hate 'em. I wanna kill 'em. Soooo...I've been poking around and saw that most people use rubbing alcohol, but I can't say I've got any kind of alcohol in the house at all except Listerine citrus mouthwash. Will that work? Will it hurt my plants?

Glen Head, NY(Zone 7a)

I don't think I would use Listerine.. alcohol is cheap enough.. I wouldn't take the chance.

Mableton, GA(Zone 7b)

I didn't use the Listerine, but thanks for your help. :)

Minneapolis, MN(Zone 5a)

Mealie bugs are one of the most difficult insects to control (along with scale). The insects will lay their egg cases away from the original plant so that even though you kill the bugs on the plant, re-infestation will occur.

When I moved in to my house from a townhouse I was renting, I had to take apart some plant stands that I built. Wherever the boards butted up against each other, the mealies had laid their eggs. No wonder I could never get rid of the darn bugs on the plants.

I use a mixture of 70% rubbing alcohol, water and dish soap (NOT detergent). I use Ivory dish soap, but you can also use Dove dish soap, too. Don't use Dawn, since Dawn is a detergent and can damage your plants.

I use a 16 oz bottle of alcohol, a 16 oz bottle of tap water (you could also use distilled water instead of tap water) and two tablespoons of Ivory. Put/mix this in a 32 oz plant mister bottle and shake gently to combine all the ingredients.

This is a contact insecticide so you MUST hit the insect to kill the insect. There is no residual action.

You may need to use more water and less alcohol on some plants with thin leaves. After spraying the plant and killing the bugs you should use a hose to spray the plant off and try to remove all of the dead bugs and egg cases that may still be present. This mixture will NOT kill any eggs. Most poisons will NOT kill the eggs either. Mother Nature protects the eggs very well.

You should spray every 7 days or so to kill any bugs that have hatched out so they don't mature and lay any more eggs.

Eventually you will be rid of the mealies, but it is a long, hard battle.

I would suggest purchasing a product called Marathon, which is a systemic insecticide that has no odor. Bayer Advanced bug killing products use the same active ingredient that's in Marathon (which is granular).

Always isolate any new plants for at least 6 to 8 weeks before introducing them to your plant collection. It will take that long before you will know if the plants are clean or not. I hope this makes sense. (c:
Good luck,
Mike


This message was edited Jul 27, 2004 8:02 PM

Mableton, GA(Zone 7b)

Thanks Mike, they are in love with my amaryllis on my front porch. They also got to some of my succulents through contact between the pots. argh. Do the eggs and stuff die in the winter?

Celaya, Mexico(Zone 10a)

treelover, your statement that "The insects will lay their egg cases away from the original plant" is incorrect, the eggs are layed within the wooly structures on the plant but the problem is that the eggs are very resilient and may not die off.

You can make a search here in this forum for mealies and/or mealy bugs and you'll find many posts about them and their control.

In short:
light to medium infestations:
1. rubbing alcohol (70% undiluted, direct or spray application[not in direct sunlight otherwise burns may occur])
2. homebrew bio stuff (1 Cup cooking oil [cheapest you can find] 2Tablespoons of diswashing soap [NOT Ultra], Mix together. Put 1-2 tablespoons of the mixture in 1 Cup of water to spray on plants)
Application of above repeated every 3-4 days for 2-3 weeks
Medium to heavy infestations:
1. Insecticidal Soap (reapply every 3-4 days for 2-3 weeks)
2. Malathion spray (low general toxicity and toxic effect disipates in a week, exterior application only, re-apply after 5 days for 2-3 weeks)
3. Cygon (Dimethoate) Systemic spray or granules (prohibited in some areas, toxic, negative reaction to some plants, lasts for approx 3 month, exterior application only)
4. Marathon (imadocloprid) systemic (expensive, some reports of negative toxic effects, last for approx. 6 month, exterior application only)
Biological:
Various mites and insects but usually only effective in greenhouses.



Minneapolis, MN(Zone 5a)

I'm sorry, PanamonCreel, but I have found the egg cases laid quite far away from the infected plant (on the plant stand that I noted above and also on window blind cords that were on the window where I was growing Hoyas (among other places).

You're correct that the eggs are laid within the woolly structures (cotton) on the plant, but they are also laid away from the main plant, too, in the same cottony mass. I believe that this is a survival strategy that has evolved so mealies will survive a disastrous event, like a large group of predatory insects finding the mealies and wiping them out (and this is also why mealies are SO DARNED HARD to control).

I have found the egg cases that were laid on inanimate objects, first hand, so how dare you tell me that I am wrong. You were not there, I was. I have grown Hoyas for over 25 years and while I don't know it all (and no one ever does) I am not a novice at this. Mealies LOVE hoyas almost more than any other plant in existence.

When I reply to someone, I am giving them my first-hand experiences with whatever I am writing about. YOU may not have had this same direct experience, but please don't ever tell anyone that they are wrong. That is not your place and like everyone else, you don't know it all, either.
Mike


This message was edited Jul 28, 2004 1:00 PM

Celaya, Mexico(Zone 10a)

I have to wonder why it is that nowhere I can find any reference on the internet (except from you here) or in books on this survival strategy of mealy bugs. Maybe it's a new discovery which has been missed by many others including me.
Mealies are very poor movers and only travel short distances and though it may be very well that you've seen egg "structures" away from the host plant I personally haven't seen that and only can imagine them very close to the host plant (rim of the pot maybe). One thing though, these egg structures easily adhere to other insects e.g flying insects which then can cause the spread of these critters. Also ants may "harvest" mealies for their honey dew and cause the spread of these guys but also that I haven't seen and only heard/read of.
I've never had much of a problem with these critters on Hoyas, with the exception of compacta in which they can find nice hiding spots within the dense leaf structure. The worst in my opinion are "haired" and densely ribbed cacti where they find good hiding spots never to be seen until "out of hand".
Also mealies may hide within the soil so do not forget to treat the soil too.
Mike, I don't really care where their eggs are hiding and just want to get rid of those guys quickly when they appear, so peace to the world.

Milan


This message was edited Jul 28, 2004 3:28 PM

Hey Mike,

My secretary gave me a gift of a Hoya. She just called me and sent me a photo of one of the plants she kept for herself and her plant definitely has scale. She ordered two plants from the same place and I have one from her order. I failed to quarantine the plant she gave me… I truly had no place to quarantine it given the time of year it is. I looked at the plant she gave me and sure enough, I can see what appears to be scale on the underside of one leaf. I am absolutely livid for having committed the cardinal sin of not quarantining the plant and could just kick myself in the butt for this swift move. Here’s the deal, I’m a member of the listserve and I have heard of others who have found the mealie eggs in the joints of both Nepenthes and Orchid hanging wooden baskets. They tossed the baskets and began using the black plastic aquatic plant baskets upon discovery. Fortunately, I have never used hanging wooden orchid baskets for my Neps or Orchids and as this is the first time I will be dealing with mealies… I am thinking there is no way I am going to allow this to get out of control. To date, I have been spared the pleasure of having to learn about mealie bugs but I suspect I am about to learn. The plants I have growing where I stupidly put that Hoya plant are Paphs, Phals, Dendrobium, Brassia, Cattleya, and one Cymbidium. Unfortunately, I also have about 30 Nepenthes growing in the same area I put the new Hoya. Mostly highlands but a few intermediates. Did I mention I cluster my plants to increase the relative humidity? Mike, I grow my plants in groupings with the rims of pots touching each other- yes, another swift move that was never cause for concern until today. So, how about giving me a crash course on mealies. I need to take a defensive approach to this situation since the infected plant was sitting on my kitchen counter by my African Violets for a few hours before I repotted it and moved it in with my other plants since Wednesday. Will you help me select a course of action please? I pulled the Hoya from the Neps and Orchids and have it in my kitchen on another counter away from the African Violets. I need a good prophylactic for all the plants I exposed to scale. I’m thinking it’s time to nuke these systemically. What are your thoughts on wettable Orthene? I’m thinking an alcohol wipe followed up with possibly a neem oil application followed by a soil drench with Orthene then repeat again in 12 weeks? Any suggestions greatly appreciated.

Culpeper, VA(Zone 7a)

This past summer I went thru a hellish experience with all of my orchids becoming thoroughly infested with Mealybugs.

Taking a deep breath, I took them all outside & thoroughly sprayed/soaked them with (organic) Safer's spray for Roses & Ornamentals. Waited a week & sprayed them all again. Waited a month & gave them one more shot.

I also thoroughly sprayed the area inside where they spend the fall/winter, paying special attention to nooks & crannies.

So far (fingers crossed), haven't seen hide nor hair of a Mealybug, & haven't had any damage/burn whatsoever to any of the plants - even the ones that were blooming while I was spraying.

Hi Breeezy! Did you have a good Turkey Day? Say, seems as if everyone refers to mealie bug infestations as Hellish experiences. I know I caught it fast and now it's just damage control. I can not go outside and thoroughly soak any plants as the temps are in the teens right now but I do have a great big shower and I have no qualms getting in there with my plants and systematically spraying them down before dousing them. None of my orchids are infested... I'm merely making sure I don't go down that road and they do always say an ounce of prevention is worth a pound of cure so I am going to nip this in the bud before anything gets out of control. The one thing I know for sure is that an infected plant was introduced to my clean plants. I suppose my number was up as pertained to mealie bugs. I am going to treat my Nepenthes with Neem oil and wettable Orthene. My Neps are my single greatest concern right now and I need to protect those. If you say you had good luck with basic Safer's Soap on your Orchids and being as how your Orchids were infested... I'll forgo the Orthene on my orchids for now. I had recently purchased a few Hoyas for myself. I have never had Hoyas before so I will wait for treelover3 to post over here to tell me whether to nuke the new plants or go for a less aggressive approach. So far the only plants I need to determine how to treat would be the African Violets. Those are throwing me for a loop right now so I posted a question over in the AV forum.

Celaya, Mexico(Zone 10a)

Your best bet is to get some Bayer Advanced Tree and Shrub insecticide and perform a one time soil drench with a 1oz BATS / Gallon of water.
This will last for about a Year, will take care of your mealies (including root mealies if there) and added advantage is that you won't get Fungus Gnats either:)

I forgot about my Tacca integrifolia. I have a few of those in there too. Tacca are touchy plants to say the least. I'm going to have to steer clear of the Bayer Advanced Tree and Shrub on the Nepenthes.

Oddly enough I never get fungus gnats in that room. I do get fungus gnats in by where I grow Drosera and Pinguicula. Springtails too. Not a big deal. Diatomaceous Earth can take care of quite a few soil inhabiting ickies and nasties.

Milan, have you any familiarity with Orthene, have you ever used it?

Yes, I am familiar with Cornell's studies. Orthene has been used effectively to treat Nepenthes for other infestations. I have no experience treating Neps with Imidacloprid.

Minneapolis, MN(Zone 5a)

Equilibrium,
You have a battle on your hands, that's for sure.

I would use the Orthene and the Bayer (or Marathon, which is Imidacloprid in granular form) to try and get rid of the little nasties. I have found that Imidacloprid will not "kill" adult mealies, outright, so I always spray the plant with alcohol, soap and water prior to treating with Imidacloprid to ensure that the adults don't lay any more eggs prior to dying.

Adult scale is immobile, but the young scale are very mobile and are the most vulnerable to treatment with chemicals.

I think using a systemic is the only way to go and you should treat EVERYTHING in your collection. I treated some plants with Marathon, that I had under lights, but I didn't treat everything and those plants that were treated were clean but the untreated plants became heavily infested.

Wash the leaves of your plants, if that's possible and then spray with the alcohol, soap and water. Then treat with one of the systemics. Also, be sure to use enough of the systemics to kill the bugs. If you don't treat with enough of the chemical you may just make the bugs "sick" and possibly resistant to the chemical and that would be really, really bad.

I wish you all of the luck in the world. You're going to need it. Just be vigilant and check the plants every 7 to 10 days to see if you see any re-infestation.
Mike

Thank you Mike.

I spent about 5 hours wiping down the tops and undersides of leaves with alcohol.

Tomorrow I will dip the entire pot of each Nep, Orchid, Hoya, AV, and a few assorted down into an Orthene mix. Oh what fun! An assembly line! Orthene should theoretically get both the soft scale and hard scale adults wherein which the Bayer Advanced Tree and Shrub doesn't always get the hard scale mealie adults which evidently you most unfortunately have already found out first hand. Sadly, you were not the first I have read of who stated the Imidacloprid was not capable of killing all adult mealies and therefore ineffective on hard scales. I don't know which scale I exposed my plants to. My secretary e-mailed the nursery and asked which species the grower had but was not given a Latin name so no sense playing with fire. I've read enough on the listserve to know that I might have to treat every last plant I have growing in those two areas so your comments do not shock me and I will do as instructed. I bought some Bayer Advanced Tree and Shrub for the Tacca, I don't think the Tacca can handle the Orthene which is a shame. Based on what I have learned, I suspect my Tacca will be toast but as you noted... they will be infested if I don't treat them. 6 to 1, half a dozen to the other but I will treat them ALL. I suppose I can try to reoxygenate the Taccas by adding a cup of H202 to their water and maybe I should pick up some SuperThrive as those are going to shock. I hate the thought of losing my Tacca but the thought of losing even one of my Neps is far worse.

After I dip each plant, I'll spray the foliage of the Neps with Neem Oil and all other plants with Safer's Insecticidal Soap. I can't use the Safer's on Neps, it's too alkaline.

Then on Monday I will flush each pot thoroughly.

I'll repeat the entire process in 10 days and hold. Orthene should have residual effects lasting up to 10-12 weeks. I am throwing out all wooden stakes I had in the Orchid pots to support blooms. Matter of fact, I think I will cut all the blooms off in an attempt to redirect the plant's energy to the roots. I think I'll just go with the green vinyl coated wire for new bloom stakes. No sense providing even the tiniest nook or cranny for these little nasties to weather out the seige. I should have done that a while ago anyway but I was too cheap when the wooden bamboo stakes were working just fine and I don't own a wire cutter. Guess I might as well pick one of those up too.

I am not going to treat any of the Drosera or Pinguicula that I had growing in another area of my home. I'm also not going to treat any of my Sarracenia. I have hundreds of those but they are dormant now and were all outside in an entirely separate area. Thank goodness for small wonders or this little fiasco would be costing me a lot more than time, fifty bucks, and the probable loss of my Taccas.

I think next spring I'm going to begin adding Diatomaceaous Earth to all of my potting mediums. Do you use this product at all?

Hey, thanks for your comments, "you should treat EVERYTHING in your collection". I had sort of been hoping for a different response but knew in the back of my mind that this was probably what you were going to advise.

Lauren

Hey Mike,
I treated every last plant inside the home. I got nervous about those little buggers possibly having hitch hiked on my clothing into another area in the home so I even did the Drosera and the Pinguicula growing in the other rooms as well as two hanging Neps. 1 tsp powder Orthene per gallon and I dipped every single plant down into the mix and let it drain. The following day, I flushed every plant a few times. Yesterday was the 10th day so I retreated at 1/2 tsp Orthene per gallon and I'll leave that sit in the potting mixes.

The Taccas are looking pretty fried. I SuperThrived them and they still aren't happy. Oh well, I suspected that would happen. One benefit to this game plan was no more fungus gnats. I had just ordered a biological control for those and got to thinking... why bother. Their happy flying rears will be toasted along with anything else that might have been incubating. And that is exactly what happened. Fungus gnats are hasta la bye bye.

I bought the Bayer product and have set that aside for now. I know to rotate chemicals and why. Given I have just completed round 1, when would you suggest I come back in with a follow up using the other product or should I bother at all as this was a prophylactic? By the way, I tossed out the Hoya. It just wasn't worth it.

wolverhampton, United Kingdom(Zone 9a)

My friend has a grape vine in his conservatory (name not known) it is some years old and produces several bunches of grapes each year. It has been infected with what I think is mealy bug, it has cotton wool and web like infection in the bud joints and is seeping some kind of sticky liquid, this infection is slowly spreading along the vines. I know nothing about this type of vine can anyone give me any help. We are not sure if we should cut back hard or just try and treat the mealy bug.

Thanks in anticipation

Sue

The web infections sound to me as if you have mites. Can you go on line and do a search and see if you can find any photos of webs to look at and see if that fits the bill? If so, I can give you some suggestions of how to nip this in the bud and I'm sure others can offer suggestions also.

Have you any friends who have digital cameras who might be able to post a photo for you?

wolverhampton, United Kingdom(Zone 9a)

Hi
I will ask my daughter to take a close up photo and post it as soon as possible. If it is any help there was a cactus placed underneath the vine which had the infestation and then spread it to the vine.

Sue

Not necessarily helpful to know there is a cactus infected also. I'm still thinking you have spider mites based on your description. You'll need to treat all the plants growing anywhere near those that are infected though.

Questions for you, on your side of the pond can you get your hands on wettable Orthene? Can you share with me the names of any miticides you have available to you for purchase in the UK? I don't know how to treat cactus for anything so if you have mites, you might want to ask cactus people what best to use on them.

Does anyone out there know if it is legal for me to send her enough Orthene to treat all of her plants if she can't get her hands on it over there?

cambridge md, MD(Zone 7a)

Do spiders feed on meally bugs. looking for a natural solution...

Minneapolis, MN(Zone 5a)

No, I don't believe that spiders would/will eat mealy bugs, but I suppose that anything is possible. I would not count on spiders eating enough mealy bugs to control them.

There is a mealy bug predator, but you'd need a greenhouse to provide the environment needed to keep them alive. It would be really difficult to use a natural (predator) control in the home environment.

A mixture of 16 oz, 70% rubbing alcohol and 16 oz tap water plus a couple of teaspoons of Ivory or dove dish soap will kill mealy bugs if sprayed directly on the bugs. This mixture is a contact control and you MUST spray the bugs to kill the bugs. Don't use Dawn dish detergent since the detergent could damage your plants.

Also, remember that no poison (or anything short of a nuclear blast) will kill the eggs. You need to be very diligent to spray and check the plants every 7 to 10 days or so to make sure you keep killing the newborn mealy bugs so they don't mature enough to lay more eggs.
Good luck,
Mike


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