Meally bug outdoors

[Andyh]

I have found that both meallybug and root meally are surviving in alpine pots eg on sempervivums and hardy crassulas, even when we had temperatures well below zero. This summer by chance I noticed meally thriving and breeding on a large mahonia shrub, and last year on passion flower (had to chop it down)
Anyone else experiencing them surviving out doors over winter? Vigilance stops them impacting on my summer outdoor and hardy cacti buts its an extra unexpected threat and a source of more pests.
Andy

[SimonT]

'Greenhouse' mealies are not supposed to survive the winter outside.
I find if I put plants outside with these pests the problem seems to go away, even in the summer.
I used to think it was just coincidence - eg the spray I'd tried finally worked.
But then I stopped spraying affected plants and the pests still vanish when the plant is put outside.

It could be natural predators but it might just be too cold and wet for mealies to get through their life cycle.

Of course there are lots of different species of mealies and some might be a bit tougher but the ones I've seen don't survive a long time outside.

[edds]

I have hung my Epiphyllum plants outside in a tree for the summer. When they were put out they were fairly infested with mealies and while it seems less, all still have some present when I've checked them. It certainly isn't a 'cure' for me but obviously I can't leave Epiphyllum out for the winter to see if a cold snap skills them off! It doesn't seem to kill them off in my cold greenhouse either though! Maybe I have a hardy form?!

[Andyh]

Like you Ive found the outdoor environment cleans normal plants, eg epiphyllums. I think its because predators can pick off the meally. I guess its the tight nit plants like sempervivums, hardy echeveria, opuntia joints that harbour them, but rarely enough to cause them grief. I suspect some spiders eat lots. Surprised to find them on mahonia, but under leaves. Sparrows roost in same shrub, but I guess they cant get to them under spiky leaves. My worry is that in the summer they will spread to plants put out of doors, greenhouse and house.
When I chopped the passion flower down there were thousands and eggs, I was coated in white !

[Paul in Essex]

There are hardy species that will survive year round and different to the greenhouse ones. Anyone who has got close up and personal with a phormium, assuming they are still alive after last winter, will have seem massive accumulations of them in the leaf bases. Whether these hardy species will do invade succulents outside or not I have no idea.

[Trilobite]

I've been working in a alpine/herbaceous perennial nursery in east Lothian for a few years now that gets hard freezes even when my home temps are borderline. I have never seen a single regular mealie but root mealie seems to have little bother surviving in many of the outdoor beds.

[habanerocat]

I've seen stem mealies overwinter for several years on a neighbours American Chestnut tree.
I lifted a patio slab one spring and found nests of root mealies underneath it. What they were living on, I have no idea, but it was definitely them.

[SimonT]

So there is also the golden root mealybug which survives outside all year around in the UK apparently.
Also various scale which are related insects and survive outside.

Most of these seem to be seen on limited host species though and different species to those that like to attack C&S in greenhouses.