Persistent Mealybug Problem

[Taceas]

I bought some orchids from an Indiana grower a couple of years ago, and thoroughly inspected each and every plant for problems. Upon getting home and getting them set up they thrived, for a few months anyway.

Then I noticed white cottony mealybugs on one orchid, a Sedirea japonica, and then on others as I looked around and in all the nooks and crannies. The Sedirea eventually succumbed to either the bugs or the various treatments I tried.

I've tried Safer's soap, I've tried the recipe with rubbing alcohol, dishsoap, and water, I've tried the systemic insecticide from Bayer...with no real success. Each time it knocks them back a little, but they always come back in a few weeks.

Right now they're mainly on one particular Phalaenopsis, down in the leaf folds near the center of the plant...and a few here and there on others. Lately I've been washing them off with a higher pressure stream of water, which does remove them and their sugary residue, but still nothing seems to kill them completely.

Is there a regimen that works? How often do you recommend treating a plant?

[Ross]

Welcome to the club! And if I haven't given you a welcome to the board, consider this it - Welcome!

My first and only bout with Mealies was/is also a Sedirea japonica. I tried Neem oil to no avail (didn't do anything.) Tried just picking them off and that didn't seem to help and I started getting worried that the critters might spread. I just tried (like earlier last week) Schultz "Garden Safe" Houseplant and Garden Insect Spray which contains Pyrethrins and Canola Oil and it seems to have worked. We'll see. I plan to spray weekly until there are no signs of infection. Mine were deep down in the leaf folds also. Just spray till soaking the leaves. This stuff should be pretty safe indoors.

[Taceas]

Thanks for the welcome. =)

And thanks for the suggestion, that's one thing I haven't tried yet. I'll look for it the next time I'm at Walmart.

For products with oils, do you leave them on for so long and then rinse them off afterwards? I'm always worried about suffocating the plant. Or are you not suppose to spray the undersides of the leaves?

Prior, I did mechanically remove as many as I could either with a toothpick/q-tip or water stream and then apply the spray.

It really is discouraging, especially when it results in the death of a once beautiful orchid. I really tried not to do much to the plant, as it was blooming at the time I noticed the infestation.

I just noticed a small one on the bud spike of a different Phalaenopsis on a completely different table, so I think I might as well treat them all regardless of whether I see anything on them or not.

[Ross]

Originally Posted by Taceas

Thanks for the welcome. =)

And thanks for the suggestion, that's one thing I haven't tried yet. I'll look for it the next time I'm at Walmart.

For products with oils, do you leave them on for so long and then rinse them off afterwards? I'm always worried about suffocating the plant. Or are you not suppose to spray the undersides of the leaves?

Prior, I did mechanically remove as many as I could either with a toothpick/q-tip or water stream and then apply the spray.

It really is discouraging, especially when it results in the death of a once beautiful orchid. I really tried not to do much to the plant, as it was blooming at the time I noticed the infestation.

I just noticed a small one on the bud spike of a different Phalaenopsis on a completely different table, so I think I might as well treat them all regardless of whether I see anything on them or not.

I just leave the stuff on (don't wash off.) It might be a good idea to spray down all the close-by orchids since the bugs are able to fly (so I've heard, but not observed.) Spikes seem to attract both mealies and scale, what is it about spikes No idea. Oh, and liberally spray/flow the spray into the medium since the eggs and babies start there.

[quiltergal]

I just discovered a single mealy last week also on a Sederia japonica. I dabbed it out of the leaf fold with alcohol and a q-tip. I've been checking it daily and haven't seen any others. I should probably stick this one back in quarantine. It arrived with the Brlla. that came with scale. I have some systemic calle Bonide that I'm going to try. I think the trick with scale and mealies is to keep treating weekly until the adult/larva/egg cycle is broken.

[Tindomul]

Welcome to the forum and welcome to the mealybug club. See my thread on this issue http://www.orchidboard.com/community...t-control.html . I think I will have to use some chemicals eventually, but not sure yet. I can tell you that my attempts at mechanical cleaning have not helped except to extend the life of my orchids.

[Taceas]

Thanks. I did read through the pages in this section also dealing with mealybugs prior to posting, and saw they didn't use anything besides what I've already tried with little success.

I did read your post and I find it nifty from a biological standpoint and something I might try should the orchids in one of my display tarantula cases gets infested (where I obviously can't use insecticides).

But most of my orchids are grown in my home and are scattered throughout the house in the available windows I've got, so unless those particular beetles stay on the infected plants, I don't want another species of bug in my home right now. =P

Tis the time of year when those danged Asian ladybugs are invading every nook and cranny in my home after crop harvesting. And before you say it, no, they don't help with mealybugs, I've tried it multiple times with little success.

I do have First Ray's Rise and Shine spray I've been spraying on the leaves and wiping off after a few minutes. It's at least cut down on the number I find, which already wasn't very many. On the Phalaenopsis in question I've only found at most 6 mealybugs at a time, and I mostly notice them when they leave the folds in the leaves for the outer edges and stick out like a sore thumb.

I'm not sure what their eggs look like or the hatching time and development time for the nymphs, but it seems as though I don't see any for a week or two and then wham, I see 3 or 4 here and there that I believe are adult sized.

I guess I'll just keep up with the spray and wipe until I can get to Walmart to look for that spray from Schultz. Frustrating bugs.

[cb977]

I use Bayer's 3-in-1. It's a concentrate that gets mixed into a gallon of water. It's a systemic and should be poured down in to the pots but I also keep a sprayer of it handy. The few times I've had a problem, I sprayed, used a cotton swab to remove the little fuzzie creepies and sprayed again...all gone

[Tindomul]

Sue, where did you get that from?

[savor]

Misty,
Since your orchids are in the house, you may want to avoid pesticides. Alcohol is effective but rinse with water soon. I use soapy or oil solutions to spray the visible insects. I then use a toothbrush and a lawn hose to get rid of them. The soaps/oils work by clinging to the bug clogging their breathing surfaces on their abdomen. They suffocate. My best advice is to soak the pot and the foliage in a container until it is saturated by the solution. Don't forget any other house plants where they may be camped out. The newly hatched mealybugs are almost impossible to see. So at the same time spray the window sill and soak the saucer too. This method has served me very well. But do spray or soak the orchids again in 10-14 days to get the stragglers.

An interesting fact: Only mature males (just 1mm in size) have wings. Newly hatched mealybugs can be carried by the winds however most infestations are hitchhikers on an orchid or other plant. For more info check out this site: Mealybugs on Orchids
Better results,
Lee

lee@classicorchid.com
classicorchidtours dot com
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