Winter Application of Horticultural Oil

Q: I have a customer that has scale on recently installed Magnolias.
I want to spray horticultural oil; however, I understand that due to recently mild temperatures serious harm to plant can occur. Once temperatures resume to “winter like” conditions how many days/weeks until I should be clear to proceed with the application.

A: Do you have a label that says you’ll get damage when sprayed in mild weather? My understanding is that spraying in freezing weather, OR really hot and humid weather is bad. Why would mild weather be a problem?

See:
Horticultural oils

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