Perhaps scale?

I was thinking whitefly?

Were I physically present to asses this plant the first thing I would look at is the growing media. What condition is that in? Is it wet? Is it dry? By far the majority of plant problems seen at the Master Gardener workshops is a growing media that is too wet which then creates many problems including insect pests.
The very simple means of correcting most of those problems is to allow the growing media to dry out.

Jane, the plant is too far gone and the image not detailed enough for us to tell you what is on your plant. I don't see any sign of whitefly, though. I'm not even sure what kind of plant it is.

Kimmsr, evaluating the potting medium AND watering techniques is always important when diagnosing plant problems. I consider it a first step.

But if you are being taught that that will resolve an infestation of scale, aphids, whitefly, mealybugs, spider mites, or even fungus gnats.....that doesn't speak well of your particular MG program.

A course textured, fast draining potting medium is essential for robust, healthy plants......but common plant pests are perfectly happy to infest healthy plants, too. A good diagnostician learns to recognize the usual cast of culprits as well as common foliage plant diseases, too.

first .. i see a window box ... with a large plant ...

then i wonder where you are ...

then i wonder what the ID of the plant is ...

and then i wonder why you just dont dispose of it.. since it will be winter

then i see you are down under.. and wonder why you didnt mention that ...

so then i think.. did you winter this over in a shallow pot .... and then i wonder how you did such ...

and then i think.. hey.. its spring for you ... why would you mess with this ugly thing all summer long... and i would suggest.. be done with it ...

and while you are at it.. dump the media... wash out the pot .... and start with some fresh media.. and new plants ...

and if you can garden in mother earth.. throw this one out back.. a leave it to the whims of ma nature... as to whether it will survive or die ...

boy.. that a lot of thinking and wondering... lol

ken

OP is from Australia, which is stated on "My Page."

Actually the OP is currently residing in Ecuador, as disclosed on a current 'Name That Plant' posting. Assume she has not been able to change her location on 'My Page' but the "ec" shows up as part of her screen name.

Not sure if that makes a huge difference except to note that plant palette will be much different from North America as well as gardening seasons.

Mealybugs! That was the one I couldn't remember the name for, LOL!

But apparently its not that either, I guess - so 2 strikes for me!