Following on from the current thread on treatment of mealy bug infestations, I started thinking that a lot of these problems might be minimised if proper quarantine protocols are instituted for new plants. Many of us are aware of and appreciate quarantine at Australia's borders, but tend to be a bit more lax when it comes to what passes our own front gates.

Quarantine is particularly pertinent to situations such as glasshouses, where plants are crowded together, and where there is at least some hope of keeping at bay the wandering pest hoards coming in from the big wide world.

As an example of this, the year before last I struck about a dozen brugmansia cuttings indoors, and moved four to an upstairs ensuite (being on tank water, the bath is never used, and the light is fantastic, so the pots take up the unused space!). Anyway, red spiders mites were brought in on some cut flowers and the downstairs plants suffered, and in spite of repeated white oiling (which makes them shed their leaves) they periodically succumb again, but the four upstairs ones are still pristine 18 months later.

So... I reckon that it'd be useful to post people's quarantine protocols, what potential pests are controlled for, and how the protocols differ depending on the species of plants grown, and whether the quarantine is of potted plants, cuttings, seeds(?), or some other form of propagule. After all, this group of threads is titled "Pests & Diseases: ID, Control & Prevention", but so far there has been no formal thread for actual prevention!

I will admit that I have not to date followed a decent protocol myself. I have simply visually checked my material as it comes in, and somewhere along the line I have introduced the mealies - probably from nursery stock, as I have since noticed them growing on the 2" pots on the shelves from where I have selected plants in the past.

Few methods are likely to be 100% effective, but if we can convince newcomers to horticuture to adopt good habits from the start, there will be fewer tears. And if we can post successful decontamination protocols, according to the species and cultivation preferences of the collectors here, we might be able to put some smiles back on the faces of those of us who have been plagued with the little monsters that we all loathe so much.

Go for it good gentles all: let's see if we can collate our collective wisdom on ways to instill some good precautionary practises in our growing of plants.

That is a good idea I think. I have always tried to quarantine new green houses and propagation. After all seedlings and often cuttings are mealy free. Unfortunately they seem to get in from some where. The adult male mealy is able to fly I can confirm this and have a picture somewhere. The juvenile crawler stage can crawl a couple of meters and also blow around in the wind. The eggs seem to be able to remain dormant for long periods too. I remember something about the female having seven generations worth of fertile offspring without needing to mate.
In all they are a difficult pest but quarantine usually works for a couple of years then preventative spraying before they become a problem is best. At present I am trying Neem extract. It is less toxic but always gives me a headache. It does't knock em down fast but I have heard it stops breeding over time. I used to use confidor (it is a nicotine molecule with chlorine added to make it more persistent.)Worked great for a season till resistance developed. Reading the directions carefully on the big bottle it says not to use for more than a season or resistance will develope. Any info about mealies is useful. Know your enemy!