I'm not sure what it is. I've treated mine with alcohol on a cotton swab quite successfully.
Marion

I had mealy bug. I was not successful(read lazy) in getting rid of it. Good luck

Is this mealy bug? I have no clue.

Marion: thanks for the advice with the alcohol. There's too much of it to apply the effort that you did, but what about spritzing it with alcohol? Would that work?
Is this the same stuff you had?

I think spritzing the alcohol would probably kill it, but would also probably wipe out the whole plant. Soap spray might work better, either Amber's recipe or a product like Safer, maybe?

Marcia

The University of Florida says that portulaca grandiflora is only occasionally bothered by mealybugs. Other than rot due to excess water, this was the only disease/pest mentioned for this plant.

Mealybug is a common pest of hibiscus, however. I would decide upon an acceptable control method that is safe for the hibiscus (systemic, biological, etc.) and then apply that to the purslane. Meanwhile watch your hibiscus closely to nip any infestation there.

There is also a pink mealybug infestion in South Florida. The literature I read indicated there is no control for it and plants infected by it must be destroyed.

Wishing you success - June

Forgot to say, this doesn't look like any mealybug I ever saw. Mealy bugs are white, softbodied critters that look more like patches of a white mold. They aren't fuzzy looking like this stuff.

Marcia

Here is a photo of mealybugs, for ya!

Ooh, the evil things!

Hate mealy bugs!

I really don't believe it's mealy bugs either. I don't know what it is, frankly. I am inclinded to think it's some kind of fungus...I'm stumped.

I sprayed some Rose fugicide on it. Honestly, it did nothing. What seems to have helped the most is the long sunny days. Most of this began in the winter when there was more of a shade shadow over the plant.

I don't know what it is either but my Purslane and Portulaca seem to get it every season. Honestly, I thought it was due to the long, hot days. I always just leave it alone. It still seems to flower and the next season it's gone and the plant looks great!

Dee

It's done blooming for the season ladies.. Trim them down for winterizing. It's not a bug, this is my 1st yr w/them & I dead head everyday to get more blooms faster. But my 88 yr old Grandma says it's done & I believe her.

I don't think it's really bugs, I'm thinking it's a fugus, and it's killing my puslane. Need help please, any ideas?

That sounds like white rust. It likes portulaca.

I can't help with the purslane problem. However, this is a great 1:38 video related to the subject:

Purslane and portulaca are related but very different

Carol in Jacksonville