That’s the question. I’ve seen discussions suggesting that you can benefit by waiting as long as possible in order to catch emerging pests at their most vulnerable. Now that it’s warming up here things are starting to happen. My apple is just starting to leaf out and my pear should be blooming very soon, maybe even tomorrow. I was hoping to be able to use the maximum strength mix but I’m afraid I’m too late.
My experience was that open leaves smothered with dormant oil will probably be toast, but if it’s just a few and the majority have yet to emerge, it should be fine. At least that was the case with my trees, which I sprayed a bit too late this year.
You gotta go to the lower rate and you should probably kill them just the same is my guess. I’m with you on waiting btw.
Now Neem oil… that stuff you can use at any stage and every 7-days if you wish.
Some of the lighter oils say you can use them all summer long. I used some after bloom one year and didn’t kill anything. (This year I did it in February…so no chance of any foliage out at that time.)