Scale insect woes

I have been having problems this season with Scale insect on Junipers. I have a basic spray from a local garden centre which is for Scale insect, greenfly and other bugs, but it doesn't seem to be working. I remember talking to a neighbour who said that modern sprays aren't as potent as there older counterparts.

Its becoming a worry as some branches have been sickening and dying back.

I think the problem has been made worse by keeping them in a greenhouse over winter.

Any suggestions of decent products or practices to help?

Please help.

Thanks!

I didn't find the right solution from the Internet.

References weetrees.co.uk/phpBB3/viewtopic.php?f=5&t=14184

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