Question about Bugs

[Tanya]

Few days ago, I noticed some of the young roots of my dendrobium have their tips been eaten by something. I could see no snails or slugs. But when I took the plants out of its pot, I saw a couple of cockroaches at the bottom of the pot ( squashed them with my foot) I wonder if they are the culprits? Cockroaches are not vegetarian, no?

Tanya

[LJA]

Tanya, actually, roaches prefer plant material as food. But they'll also eat decaying organic matter, and have been known to eat bones, glue, sandpaper, ink, wallpaper, even the shielding on electric cable. So I'm sure your dendrobium roots must have been like caviar to them!

Mix up some insecticide and pour it through the pot a few times, catching the runoff and pouring it through again. They might have left egg casings in the medium that would be hard to differentiate from a piece of bark, and you want to get those before they hatch out.

[Tanya]

Thanks Louis, I have never thought that the roaches are my enemies. Except for my Phals and a couple of phaps, all my orchids are growing on the roof, no space for them indoors. So they are expose to whatever winged creature that decide to visit. It is common to find one or two roaches from time to time and I spray the place everytime but never on the plants !!! Dumb me !! Now I know who is also responsible for the colmanara. Thank you so much for the info.

Tanya

Ps,
Hubby thought its the tiny millipeds that are to blame so he went about killing every millipeds he could find...another dumb creature...lol

[LJA]

No problem, glad to help. Just be sure the insecticide you use is okay to spray on plants. Many household insecticides will hurt plants, so be sure to read the labels before you use them... As far as the millipedes go, they also eat decaying wood and plant material, so it's a good thing to get rid of them too, if you can.

[Tanya]

I have never used chemical (insecticide) on my orchids. But I still have Dimethoate 40, left over from when I still have a small garden ( thats before we move) Is it safe for orchids? Its a systemic insecticide. I know now that I can't use Baygon for plants, I learned that long time ago... sprayed on Dahlia and zapped the dahlia quick...lol.

Thanks again,
Tanya

[LJA]

The Dimethoate should be fine. It's a systemic and it also kills on contact. I don't know how long an opened bottle can last before expiring though, so you might want to get a new bottle if yours has been open for a few years.

(You probably already know this, but, Dimethoate absorbs really easily through the skin and lungs--it's powerful stuff. Wear a mask, gloves, and protective clothing when you use it!)

[Tanya]

Ok, I dumped the Dimethoate, its 2 years old..lol. I found another chemical at the farm shop this afternoon, Malathion, its contact and milder. I just hope its strong enough for the roaches though. Now I just have to wait for a cooler day, where are those clouds when you need them?

[LJA]

Malathion will definitely do the trick, no problem. Glad you dumped the other....

[lupita]

Hello.
Are there other fungicides that are less toxic to humans but as effective to destroy cockroaches ? that I can use ? Any you could recommend?
Thanks.
Lupita.

[Brutal_Dreamer]

Hello.
Are there other fungicides that are less toxic to humans but as effective to destroy cockroaches ? that I can use ? Any you could recommend?
Thanks.
Lupita.

Hi Lupita,

Fungicides will not kill cockroaches. You could get cockroach traps for that.

Cheers,
BD