Yes, the key is getting good coverage, especially on the bottom sides of the leaves. I have found one that works great up to 92 degrees with no burn, (Saf-T-Oil). I don't think it is available retail. I buy it in 2.5 gallon jugs.

Another good product is 'Ultra-Fine' available at most hardware and home improvement centers. It is a solution made of emulsified parafin that mixes with water and can be used anytime, at any temperature. Sprayed on the bottom of the leaves, it suffocates the bugs. It is not a pesticide chemical, so it is environmentally friendly, you could fry an egg in it.