Except for the kiwis and possibly grapes, -3C is absolutely no problem for unopened buds, or even opened flowers of some.

Kiwis especially are very frost tender, so it just depends how far along they are. In my experience anything beginning to emerge from the kiwi stems have been killed by even mild spring freezes. Grapes would probably have to be fully leafed out to get seriously damaged by those temps.

Then again, the weather forecast is only a guess, and it never says how long those low temps will last. 12 hours steady at -1C would probably be worse than a sudden dip of 3 degrees below in the four hours before sunrise.

Good luck to you!

The Arctic beauty buds are swelling, still a sortve reddish purple. The Issai, there are smallish green dots on the large bud nodes. I dont see any legit "growth" on them.

The grapes are budding, but they are at that stage where they are just swelling, and you can tell they are alive, not leafed out.

I should say my last frost is from may 15 to june 1, so any time within the next 2 weeks. This isnt out of the ordinary. The record low is -8C.....

This is probably the best chart for your purpose

Although it doesn' list everything

Here is a link that might be useful: Bud hardiness chart

Oh man..... Thanks for the chart!!

Showing 32F here on Sunday morning...what sucks is there should be a lot of wind, so protection is going to be tough...

I have some kiwis with leaves already...better protect them.

Grapes will take a light freeze just after bud break. But they don't have to be very far along to get nailed by a very light freeze. I don't have experience with Kiwi and freezing weather but suspect they are as tender as grapes or even worse. They might take 31-32F for a short period if overcast. But could get nailed at 35-37F with a strong radiation freeze.

Thanks for the advice every one. I guess just to be on the safe side, Ill mulch the kiwis the night ts supposed to dip.