SJN,

Once you cut the stalks down to soil level, you've lost your chance for blooms this year. Most heliconia bloom on second year growth (Psittacorums are the exception). I get an outbreak of scale late in the winter on my greenhoused heliconia. When Neem doesn't do the trick, I use Orthonex. You might not like the chemical thing but it works. I don't know about digging them up and treating the rhizomes. I've never done that to combat scales so I'm not sure if that would be effective or not.

Steve

Just use a good systemic, like Orthene, in addition to your Neem Spray. Keep it localized to avoid getting it onto other plants and decimating your beneficial insects, and water with the solution as well, instead of digging up your rhizomes.

One thing to remember is, scale insects usually don't just go and fall off after they are dead. Are you certain you have live ones, and are not just re-treating dead ones?

The way to tell is, when you squish one, is it "wet" or "dry"? Wet ones are alive, dry ones are dead. Dead ones should just flake off with your fingernail.

For Neem to be MOST effective, you have to use it once every 5-7 days for 4-5 treatments, and you have to remove the dead scales in between treatments.

Why? Because the eggs are laid under the protective shell, and even in the adult gets the ax there may be viable eggs that hatch out later.

A lot of varieties of scale live in the soil and go dormant over winter. That's why just as you think you've got it under control, it's back in full force. So if you do decide to whack them down, I would scrub and dunk the rhizomes and dispose of the soil.

My personal preference is spraying them with rubbing alcohol. If you buy the large bottle a "squirter" off of anything else will fit it perfect. Works great if you catch it very early, if not scale is a royal pain.

Thanks for all the sound advice. I have used neem every 6-7 days religiously for the past month and I keep finding new tiny ones that squish. Is the orthene the same as ortho systemic? I tried the ortho at first (before the NEEM) and it didnt seem to work.
I would happily give up blooms to get rid of these suckers lol. I just dont want to totally kill the plant. It used to be so lush, now its leaves look stunted and I took off most of the old ones because they had the scale first.
I have found a lot of dead crispy scales, didn't realize I had to pick those off too!!-- fun fun ! I think scale must be the worst thing to get rid of-hate those things. When I cut off some of the older stems I found scales down in the hollow/rolled up parts so if I could put a systemic into the roots hopefully it would take care of that. But how would I pick them off when they are inside?
SJN