Hi Kniles-
Actually, I just did my Kocide 3000 & dormant oil spray today for my apples here in zone 6b. But, Im talking apples, and youÂre talking cherries and stone fruits, so IÂm not sure my experience will cross over.

Two questions:
1) Which of the two ingredients are you worried about applying late? the oil? Or the Kocide?
2) Which diseases are you trying to fight with the Kocide?

For me, I use All Seasons horticultural oil which you can even apply in the summer. (Not sure if this is best oil or not) So, for me, my oil is not a limiting factor though I do have to reduce the amount that I use as the season gets later. Also, my label doesnÂt technically say the usual "must stay above 40 degrees for 48 hours". It just says "Make application when the temperature is above 40 degrees". Because I never knew about that 48 hour window, I didnÂt even try to abide by it until this year. That said, I still couldnÂt satisfy that when I sprayed today. It was about 60 degrees (with a bit of a breeze) when I sprayed, but the forecast is calling for 35 degrees tonight though, I usually seem to be 3 or so degrees warmer than the forecast.

Reading the Kocide Label, it seems pretty clear when you can apply it. Are you trying to get your last dormant spray in? Hopefully others will have some thoughts here as well.

Below are my notes from today on my Kocide and oil spray (again for apples though). Not sure if it will help.

Also, IÂm a newbie at all this, so take any advice I have with a grain of salt, and read your labels!

-Glenn

4/15/09 Â Kocide 3000 (for scab) & dormant oil & deer spray.
Copper: I used a 2 tbsp/Gallon Kocide 3000 rate
Oil: Used the 4tbsp/Gallon rate as recommend by Scott. (backed rate from earlier spray because itÂs later in season)
Deer Spray: Used 1 cup/gallon of Liquid Fence.

GlennÂs notes: I made a sprayer full of 1 gallon of water. First, I just mixed in the oil & deer spray. I used it on the Liberty, Williams Pride and Enterprise, plus the blueberries, serviceberries. This took up about half of the gallon. Good. Then I mixed in the Kocide for that 1/2 gallon. I used a 2 tbsp/Gallon rate (though I may back this down to 1.5 or 1 per Scott/Jellyman next year)Â but, since itÂs only half a gallon, = 1 tbsp Kocide. I then sprayed all the remaining apple trees, peach bush, and gooseberry. This left very little in the sprayer and was about the exact amount. Nice. The forecast says 35 for tonight, so IÂm not inside the oil 40 degree window, but IÂm finding weÂre usually a couple degrees warmer. Hopefully that will be OK. IÂm also doing the oil at the same time because it acts as a sticker for the Kocide. IÂm thinking this is the exact date that I want to do for the 2nd Kocide treatment in the future because there are only a few green tips. This may also give me a little Fire Blight protection.

Related quotes: "Another Kocide & Dormant oil spray just prior to, or at bud break (green tip) for scab" -JM "Early April Horticultural oil to kill Winter Moth eggs" Â HM?

Kniles:

You should still be ok to spray these materials full strength for a while in zone 5. You don't have any leaves pushing out yet, or do you? That's really the controlling factor -- the stage of leaf development.

Don't wait for the perfect window to spray, or it may never come. Don't worry about 48 hours above 40; that's probably rare at this time of year where you live. If you get a nice, sunny day, spray. Rain is a different prolem. It would be nice to have 2-3 days running without rain, though not all the spray will wash off, and it will have done most of its job anyway.

The biggest bugaboo I have when spraying is wind. I dislike spraying when winds are higher than 5 mph, and prefer calm winds. I get a lot more of the product on the trees when winds are low, and less on the ground. Less to blow back at me too. When I have a calm day and timing is still pretty good, I get out there and spray.

Don Yellman, Great Falls, VA

"You should still be ok to spray these materials full strength for a while in zone 5. You don't have any leaves pushing out yet, or do you?"

I'm expecting my zone 5 to be in full bloom this week. Small leaves have been poking out here and there for a while.