Scale After All These Years :(
 

I've been growing orchids for 20 years and today I noticed a scale underneath one of my orchid's leaves. I used a Q-tip w alcohol and removed but I'm concerned about my other 21 orchids. I did recently purchase BioAdvanced 3:1 and fortunately it still has a bit of Imidacloprid.
My plan is to take all plants outside and spray liberally, repeat in 2 weeks X2.
Sound like a good plan? Any other suggestions?

If you have other houseplants, treat those too.

I would recommend shortening the treatment interval to a week. 3 treatments should do it.

I do have a concern, I read Imidacloprid can be toxic to cats and my cats on occasion nibble on the leaves. I also read it is the same ingredient as topical flea medicine but can't find anything specific to ingesting plant foliage treated with Imidacloprid. Thoughts? Thanks again for all the input - Melanie

There are other products that are applied as a root drench. So long as your cats aren’t soil diggers, they shouldn’t come into contact with it that way. Check your label in case yours can be used like that.

For very few scale I use either soap solution or 70% alcohol, but not a mixture of the two. I then pay very close attention over days to weeks to figure out which plants still have them. The infested plants I will completely submerge in a weak soap solution for 4-12 hours.

Scale females lay eggs under their shells. Treating plants is enough. Mealybugs crawl far away to lay eggs, so they are harder to control.