Greenhouse: help - My new greenhouse has spidermites/ white flys , 1 by jimrader

jimrader wrote:
I am very thankful for all of your help, thank you !
I am standing by
trying to figure what to do next

I have a 4 foot Brugmansia in the greenhouse which is bloombing and has a smattering of whiteflies. A couple of bananas which are also looking fairly good

It appears that I should remove more infected leaves and probably all of the Columbine growth because it all looks like the photos. I removed all of the plant to the ground on the worst of them 3 weeks ago and they now have about 1 inch of new healthy light green growth, no sign of insects !

because there are also a few adult white flies I feel that I should spray to prevent them from multiplying ?

The neem based product does not seem effective on plants as infected as my columbine

so I tend to feel that I have sprayed once (The malathion)
5 days ago

looking at the 3-4 day rate at which the whiteflies reproduce it seems to me time to hit the next group as they hatch.

you mention dormancy, do your deciduous plants drop their leaves in the Greenhouse during the winter ? what triggers dormancy ?

my green house is heated and I don't expect it to get below 50 in the GH this winter
our average low is in the 50s dropping to the 40s in december
our first frost is months away (Jan - Feb)