saw 1 adult mealy, how worried should we be? - Orchid Board

tmoney · #1 10-16-2021, 04:52 AM

hey all,

so we just got back from a week away and this morning did the usual watering routine for the plants. on one of our phals i saw what was for sure an adult mealy bug in the middle of a mature leaf. immediately got rid of it and washed the plant. but with only one adult mealy seen on well over 100 houseplants, how worried should we be that an outbreak is imminent?

thanks!

Ray · #2 10-16-2021, 08:16 AM

Treat them now. Spray and media drench. Any delay will allow the population to explode, making them harder to eradicate.

estación seca · #3 10-16-2021, 12:54 PM

Mealy bugs are like crooked politicians. There are thousands for every one you notice.

Orchid Whisperer · #4 10-17-2021, 09:04 AM

Find a systemic insecticide (I recommend those containing imidacloprid). As Ray said, treat the medium as well as the leaves etc. Repeat per instructions on package.

Treatment should include any plant (not just orchids) that are anywhere near the plant where you spotted the first mealybug.

In my experience, trying to treat mealybugs and scale insects with soap, Neem, etc., (any thing other than a systemlc insecticide) is futile.

The website of the St. Augustine Orchid Society has specific recommendations for pesticides and their use.

tmoney · #5 10-17-2021, 01:58 PM

thanks for the input all...any of you european folks got good input on a pesticide available here and where i could get it from? i really hate to use chemicals, but mealy and scale scare me worse.

camille1585 · #6 10-17-2021, 03:19 PM

Quote:

Originally Posted by tmoney

thanks for the input all...any of you european folks got good input on a pesticide available here and where i could get it from? i really hate to use chemicals, but mealy and scale scare me worse.

As far as I know, imidacloprid is banned in several, if not all EU countries. In the Netherlands I couldn't find any systemics at all anymore so I used an horticultural oil to treat my collection against mealies this summer (this is an ongoing issue since 2008...) I did 4 applications a 1 week intervals, spraying all leaf surfaces and now a month later I'm seeing mealies again... Luckily I found a new systemic for sale (one of the rare chemical insecticides in stores) that I will try, but probably not until next summer. I don't like using chemicals indoors and its too cold now to treat the plants outdoors.

Leafmite · #7 10-17-2021, 03:48 PM

Cold-pressed Neem oil works well. Some people make a mixture with isopropyl alcohol and a a little dish-soap. I have this on hand but I have been using insecticidal soap that is safe for indoors.
My plants were really infested last spring so, as soon as it was warm enough, I threw away the very worst and put the rest outside, then ordered lacewing eggs and lady bug larvae. They did a very nice job cleaning off my plants during the summer. I spotted some lacewing larvae on my plants after bringing them inside so I am hoping they will keep any issues under control. Usually, I find lady bug larvae so I am hoping I have a little army of biological control.

I cannot use systemic because nearly all my plants produce edible fruit or have leaves/flowers that can be used in tea. The orchids and Carnivorous plants are the only exception and it wouldn't be good for the latter and the spent flowers of the orchids are enjoyed by our guinea pig.

Fuerte Rav · #8 10-17-2021, 07:08 PM

I get Cochineal which I think is similar.

Neem/horticultural soap mix works for me on my orchids (inside). Water plant well first, then drench complete pot and spray all leaves both sides and any inflorescences (doesn't seem to damage flowers). I do it in the shower if it's cold outside. I love the smell but it makes my dog sneeze!

For outside I use a product called Piriproxifen 10. It's nasty stuff - mask, gloves etc. I always spray after the bees have gone.

Repeat either treatment weekly for 3 or 4 weeks.

Good luck!

tmoney · #9 10-18-2021, 01:51 AM

duuuuude, you guys aren’t making me feel all warm and fuzzy inside!

so, ok, time to get some need oil and horticultural soap. thanks fuerta for the cochineal suggestion, we will look for that as well.

also camille, would you be so kind as to pass along the new one you are trying? we will go the less toxic route thru this winter but if that doesn’t work then we might be in the market for some bigger guns

camille1585 · #10 10-18-2021, 03:07 AM

Quote:

Originally Posted by tmoney

also camille, would you be so kind as to pass along the new one you are trying? we will go the less toxic route thru this winter but if that doesn’t work then we might be in the market for some bigger guns

I'll have to go down to the basement to check the product label, but I think it's Sanium, from Protect Garden (Bayer).

I have a neem oil product that I'll try now and through the winter months.

A question about Neem and horticultural oil based products : can you drench/soak the pots in it? The horticultural oil stuff left a nasty oily coat on my plants, and I'm afraid of suffocating the roots with it...

Tmoney - if your plants are sitting in saucers, be sure to check the underside of them! I usually find many on the underside and under the lip of the saucer. Also check your grow area. I found them in the nooks and crannies of my shelves too. (And under sofa cushions, in my sewing box, in the box of orchid supplies under the shelves...)