If you blew on these dry flakes would they come off?

This may be powdery mildew or possibly foliar mealy bug.

Take a Q-tip and dip it into a bottle of rubbing alcohol. Touch some of the white places and look for the reaction. If it is foliar mealy bug, you should be able to clean up the plant with the Q-tip in alcohol.

If these dry flakes blow off, it is probably just debris. Take an artist's paint brush ($1.00) at the dollar store and wisk off the flakes.

If the flakes don't react to alcohol or to the wisking, it could be powdery mildew. This can be taken care of with milk diluted in water and painted onto the leaves. Or you can get an antibacterial spray. For just one plant I would not invest in expensive chemicals to cure this.

nancy

Powdery mildew looks like spilled flour on the leaves (and the base of the flowers). The simple way to get rid of it is to spray with Lysol -- it'll damage the flowers, but the plant'll be happier. The trick is to hold the plant 6-8" from the spray, so it kind of settles on the plant; this helps avoid damage to the leaves from the cold liquid.

Then see what you can do to improve your air circulation.

Hopefully it's not bugs, they're much more difficult to destroy.

Good luck.

Korina

Hmmm, these are pretty good ideas but I don't think that's it. Maybe if I gave you more information....

These AVs are situated under a grow light that gives them 16 hours of light per day. They are blooming like CRAZY and are extraordinarily healthy-looking but for the dandruff. Is is possible that the dandruff might be residue from the phenomenal amount of blooms? Like, maybe the blooms just kind of EXPLODED... or (and my ignorance of AVs is showing here) if the seed sets, matures and dries, maybe it's some sort of husk remnant? Is this even possible?

The dandruff does brush off (well, considering the leaves are kind of furry that is) and it kind of just lays on the leaves like debris, as robitaillenancy suggests. Thing is, no other plant types on that shelf are similarly affected, just the four AVs. It's not on the immature (read non-blooming) AVs, just on the 4 that are blooming like crazy. These 4 are different colors and at least three of the 4 are affected so.

If powdery mildew on AV looks the same as powdery mildew on say, Monarda or phlox, then no, that stuff is much more a "part" of the plant, whereas my stuff is more like a remnant left behind. But then again, better air flow wouldn't hurt!

Sixteen hours of light is what we give for taking plants to show. You may need to reduce that light an hour at a time so the plants don't spend themselves and stop blooming for a period.

I would just brush off this debris with a soft paint brush. I'm pretty sure it's no bug.

Nancy

Could it be thrips? The flowers that are open, look close and do you see any movement, small thin white or brown quick moving, hoping insects? Could the pollen be "spilling" from the blooms, is the dust yellowish? I have a bird in the room with my plants and it makes a mess of debris on some of my plants. Hope you can find out what the plant problem is! tish

Thank you for the suggestions.

I will check for thrips. Not sure what it is that thrips do, but I suspect the problem is because the lights have caused the plants to produce MASSES of blooms.

I will reduce the light. This is the first year I put my AVs under light and they're just there with a bunch of other (but light-loving)houseplants. How many hours do you recommend for regular growth on AV's? I'll move them to another shelf.

Reed Greenhouse has info help that has pictures of leaves with problems and also insects and insect damage. Maybe that could help you identify your problem. I've never had debre on leaves from plants flowering too much unless the blooms have died and dried up. You wouldn't notice thrips on non flowering plants, mostly you see them moving around on the flower petals and a lot of pollen is "spilling" out....a close look and its pretty easy to tell if it's thrips. If you don't think it's powdery mildew either, maybe you could post a picture and we'd have another idea. Do a search on lighting, there have been many posts about how much light, distance from the bulbs, etc. Hope you find an answer to your problem. tish

Per lily-pad22's suggestion, I looked closely at the affected plants and 3 of the 4 showed no inhabitants on the blooms or on/under the leaves. The 4th one, however had a couple of tiny green soft-bodied critters, probably aphids (?) on the bloom stems. I double-checked the three and again found no multi-legged lifeforms. So, that at probably explains why some of the blooms aren't reaching maturity. As to the dandruff, when I web-browsed for "aphid control for AV" I found "You may see small white specks on the foliage. These are not live insects but are the old cast off skins of the nymphs as the progress onto the next stage." THANK YOU for your suggestions. Gotta get me some insecticidal soap!

The "dandruff" is very likely to be cast skins of aphids.

And you found them -- "tiny green soft-bodied critters" -- they're very tiny, aren't they?

Beyond that, good job in locating the answer to your own question!

Oo, aphids; I've had aphids before, and they're so ridiculously easy to kill, but difficult to eradicate.

Give your infested plant a spray of rubbing alcohol. Yep, plain ol' alcohol. Kills 'em d-e-a-d. The cautions: never enclose a wet plant (they turn to grey mush); keep the plant away from drafts until it dries, so it doesn't catch a chill; you will need to spray again 2x a week to get the hatchlings; be sure to spray waaay down into the plant to get them all; and try not to breathe too much fumes.

Good luck,

Korina

jean001, thanks for the kudos, but it's you guys who are deserving of them.

korina, I bought some insecticidal spray at the store. Tried it last night. If that doesn't work, will try spraying that alcohol and if that doesn't work, will try DRINKING the alcohol! Thanks for the 2-week advice; now that I know what I'm dealing with I can stay on top of it.

Funny, but AV's always had a "little-old-lady"-ish feel to me. Either they've gotten waaaaay more sexy in the past few years or I've turned into a little old lady. Probably both.

LOL o no, that means, I've turned into a little-old-man.
~tom

Does anyone have a photo of the 'dandruff'? I have a large Jade plant. Even when I look at the dandruff under a powerful lens, I don't see any bugs. The scales are scattered in areas of the plant & don't seem to cause problems - everything looks healthy. What am I missing?
~ ithrive

Doesn't jade just do that? I have a jade, and it just periodically gets these white scaley flakes. I think someone said that that is mineral deposits 'sweating' out of the pores of the jade now and then. It also sometimes happens when I let it get too dry here and there (yes, I've actually let jade get too dry... whoops. Lesson: don't put it where you can't easily see it, ha.)

I don't think it is related to the problem the OP was asking about, especially since you say it looks healthy otherwise and you can't see a trace of bugs even under magnification.