I agree on the ID. There are many different monstrose strains of this species, there's a lot of variation. Some remain quite compact, they produce tons of offsets and grow into a blob, others can get really big - and there's everything in between. This looks to be an in between one, so it's hard to ...

Looks like M. plumosa to me...probably.

No cactus produces a blue pigment, Those that appear blue have a waxy "bloom" on their surface that scatters light, and short-wavelength blue light is scattered more than other colors. Gymnos don't produce a waxy coating.

Seems to be a fairly variable species. I'd say close enough.

Agreed.

Even Vancouver Island is pretty frigid right now - but nothing like Calgary!

No doubt. Kept in a very bright location, I take it, from the color and heavy wool production.

Yes, alcohol will kill them, as will soap sprays. The eggs will survive, though, and more will hatch out - you need to repeat the treatment weekly until you're sure they're gone. The advantage of systemic insecticides is they have residual action, they will continue to kill the new hatchlings for mo...

If you can't keep it cold enough it may need a dribble of water once a month or so to keep the roots alive, but the ideal would be to keep it cold once it gets dry (they can even take some frost when dry) and give no water at all - that's the way to get the most abundant flowers.

It's growing when the light is not good enough, which is why it has those skinny tips. Also, it needs a winter rest if you want it to bloom. See: http://www.cactus-art.biz/note-book/Dictionary/Dictionary_W/dictionary_winter_rest.htm If you can't provide the cool temperatures recommended you should s...

They look great! Nice assortment.

The cactus is big enough that it should fill that pot with roots before long. Be extra careful with watering for the first year or two - make sure it's really thirsty before you water it. I have been watering it every 20 days give or take a day. It has been sending out a lot of roots in search of s...

The cactus is big enough that it should fill that pot with roots before long. Be extra careful with watering for the first year or two - make sure it's really thirsty before you water it.

The taxonomy of that species is controversial, and it's quite variable, but I think that's correct.

You shouldn't heat the potting mix enough to completely sterilize it, more accurately you pasteurize it - hot enough to destroy fungal spores and weed seeds, no hotter than 140f - 180f is needed. Enough heat to sterilize the soil totally will not only eliminate beneficial microbes, it can produce to...