SSG, yesterday would have been a good day to take it outside and wash it off. You might want to wrap a bag around the pot, and tip the stems over a sink, and hose them off. Pick out the worst stuff. And scrape off the top of the soil and get rid of it.
I have some trouble keeping begonias happy. Sometimes they are great and sometimes I really struggle.
I gave my Brug cuttings a shot of Bayer flower food with systemic, after spraying for mites. I figure, under lights, the Brugs would want to grow and would use the food. They are rebounding but I don't think the mites are really gone. You can never assume you've conquered spider mites.
I found a ton of orange aphids on my tropical milkweed cuttings a few weeks ago. I cleaned as best I could but am still finding a few popping up.
