Updated with photo, for what it's worth.
I got out yesterday after work and wrapped my fruit trees and currant bush, but I forgot about my raspberry and gooseberry bushes (luckily it didn't end up freezing last night). I don't have any way to get any sort of cover over them, and it is supposed to be in the 20sF early tomorrow, Tuesday morning.
I'm not what sure do. I guess I could set an alarm for some time in the middle of the night to check the temperature, then if it is trending below 30°F, run the hose spray over the bushes, hopefully making ice that would coat their leaves at 32°F rather than dipping below that.
Another option would be to put one of my temperature sensors out near the berry bushes to see what kind of microclimate I've got there, and then if that drops, protect them with the water. Those bushes are generally more protected by structures and the lay of the land than everything is out front. Maybe that area won't hit the freezing mark?
This is #Kansas, so I'm used to losing fruit crops because the weather in April didn't cooperate.
This dip tonight means we likely won't get any peaches or pears from local trees unless farmers go to extremes to try to keep those from freezing. I don't remember having Kansas peaches more than one time over the last 10 years because of April freezes.
Peaches seem to be the most sensitive, which is part of why I've never planted a peach tree. 
Was sie fand, war aber kein Monster, sondern ein echter Mann! 
Der Eindringling wurde festgenommen. 
Mehr dazu hier: 
