Mineral mix preventing root mealy bug?

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Robb
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Mineral mix preventing root mealy bug?

Post by Robb »

I keep getting root mealy bug on some of my Turbinicarpus plants, and I don't like to having to re-pot them every time at risk of damaging their roots. I've read somewhere that using a mineral mix can prevent it, is this true? If so, what should I use to make it? (I have pumice and larger sized lava rock readily available)
Cheers!
Robb.
Buying a cactus a day will keep the madness away.
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adetheproducer
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Re: Mineral mix preventing root mealy bug?

Post by adetheproducer »

I use a pure mineral mix with my turbs and never had mealies on them. I have had a few plants with infections from the nursey which is quite common but once cleaned and repotted in peat free mix I have no further problems. I thinks its more to do with the cacti's reaction concentrating sap and toughening skin in the harder conditions.
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Steve Johnson
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Re: Mineral mix preventing root mealy bug?

Post by Steve Johnson »

Soil-less mixes are a remarkably inhospitable environment for root mealies, so I would agree that pure mineral is a great way to avoid the problem. While there's no 100% guarantee here, cacti in the peak of health generally aren't attacked by mealies either above- or below-ground -- that's why pure mineral mixes really help to keep your plants free of pests and disease.
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iann
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Re: Mineral mix preventing root mealy bug?

Post by iann »

I stand on my head every morning and don't have mealies ;) You keep getting root mealies because you have root mealies and you're not killing them all. Repotting into different soil won't change that, although it would be an opportunity to check out the problem and give everything a good clean. Kill them all and then it won't matter what soil you use. Not that I'm telling you to put Turbinicarpus in a rich peaty soil, you understand.
--ian
keith
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Re: Mineral mix preventing root mealy bug?

Post by keith »

I switched to using 1/3 diatomaceaous earth the kind used in pool filters mixed with 1/3 pumice and 1/3 desert soil to get rid of root mealies. Didn't work they still showed up.

It did get rid of sciara fly. And some of my cactus grew much better. Some grew worse. Most turbinicarpus grew worse. Epithelanthas grew better.

Imidacloprid works well for root mealies not as well for above ground mealy bugs.
keith
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Re: Mineral mix preventing root mealy bug?

Post by keith »

I found this online. I use food grade D.E. and have been for the last 6 years or so. Before that it was swimming pool stuff that was heat treated.

Pest control[edit]
Diatomite is used as an insecticide, due to its abrasive and physico-sorptive properties.[8] The fine powder absorbs lipids from the waxy outer layer of insects' exoskeletons, causing them to dehydrate. Arthropods die as a result of the water pressure deficiency, based on Fick's law of diffusion. This also works against gastropods and is commonly employed in gardening to defeat slugs. However, since slugs inhabit humid environments, efficacy is very low. It is sometimes mixed with an attractant or other additives to increase its effectiveness. Medical-grade diatomite has been studied for its efficacy as a de-worming agent in cattle; in both studies cited the groups being treated with diatomaceous earth did not fare any better than control groups.[9][10] It is commonly used in lieu of boric acid, and can be used to help control and possibly eliminate bed bug, house dust mite, cockroach, ant and flea infestations.[11] This material has wide application for insect control in grain storage.[12]

In order to be effective as an insecticide, diatomaceous earth must be uncalcinated (i.e., it must not be heat-treated prior to application)[13] and have a mean particle size below about 12 µm (i.e., food-grade – see below).

Although considered to be relatively low-risk, pesticides containing diatomaceous earth are not exempt from regulation in the United States under the Federal Insecticide, Fungicide, and Rodenticide Act and must be registered with the Environmental Protection Agency.[14]
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Robb
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Re: Mineral mix preventing root mealy bug?

Post by Robb »

Thanks for the input, everyone! I think by plants keep getting root mealy-bug because of all the ants on one of my benches. I read in a book that ants can transport the bugs from pot to pot. Next week I'll try and buy some pumice and diatomaceous earth as well as some new imidacloprid. Hopefully I can beat this problem once and for all :D . But would it be safe to re-pot the cacti now considering that winter is just around the corner for me?
Thanks again for your help!
-Robb
Buying a cactus a day will keep the madness away.
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