Rob, yeah I thought the same thing, even black plastic, any thing to keep the lightbulb heat in at night and sunlight out during the day ( I used clear plastic). It would be nice to cover in Dec. and not worry about it until late Feb. Good ole el nino really helped, 4 nights of monkeying around wasn’t too bad.
Mine too, can’t wait until Wed to push them out and watch em pop. Last year I did it a little to early for my Mericrest nectarine and it died back to the trunk
We’re supposed to get to 27 tonight, and I don’t have much fruit forming, so I used a double layer of bubble wrap and taped it around my little fruitlets. I also have a just-post-bloom pear that I did the flower clusters on. I covered the blueberries completely because mine aren’t that tall. My brambles and strawberries are fending for themselves, so I hope that works out. Later strawberries are fine enough with me.
Hi Chris, I think the webcam is a feature of Weather Underground, not of the weather station. If you hook up a webcam to WU you will see it along with the station.
So far I have been really impressed with the station. The only downside is the $300 price. I almost got the cheaper non-wifi model but I couldn’t put the console in the spot I wanted as it needs an Ethernet port. These temperature alerts are really useful, I don’t have to stay up all night monitoring the temperature. You can also set alerts for high wind and large rain accumulation, I plan on doing that as we get problems in both cases. I had a cheap Oregon Scientific unit but it was a piece of junk. These Ambient Weather units are supposed to be a lot more durable, we will see.
I was out inspecting my orchard and covering the poms, it looks like I lost a fair amount of my apricots in earlier freezes. The little fruitlets are browning. There are some good ones but many more bad than good. Some of the peaches are also toast. I have a couple varieties with the double blossom flowers (e.g. Red Baron) and they seem much more frost adverse - it seems all the fruits are dead on them.
So how do you think you did? Looking at your obs you dropped to 27F, but weren’t there for very long at all… BWI (airport in Baltimore) dropped to 26F but only briefly…
Rob, Omaha is in the clear for now. 70 degrees today. I got 90% of the blooms saved on pluots, peaches, and plums. What a relief!!!
Tony
Good job! You guys stayed just far enough west of this garbage to dodge the brunt of this latest plunge. I’m going to look mine over and see if anything was damaged. Extended looks very nice for you and that heat should be creeping up here as the week progresses… NWS here said my 2 favorite words…Omega Block (a pattern that locks in warmth for more then a day)
Very warm/mild long range… Cold air is all getting kicked out over the Atlantic…good place for it.
Ray,
Wanted to let you know I called the number or their website a couple times Friday. The owner “Chalmers” was in a meeting then out. I’m thinking w/ 500,000 peach trees, this guy is probably as busy as the president of the U.S.
I have been reading a little more about frost protection measures. I found what I think is a pretty good online resource which may answer some of these questions (especially as it relates to preventative sprays).
Here is a link to one of the chapters. (Scroll down to the bottom to read the section on bacteria control. The author discusses other sprays in that section too, but more importantly discusses how freezes kill flowers.)
http://www.fao.org/docrep/008/y7223e/y7223e0c.htm#bm12.13
I had wondered why the label of Kocide indicated it must be sprayed at least 24 hrs. in advance of a frost event. Turns out it’s the amino acids in the bacteria which start to form the ice crystals. After killing the bacteria, the amino acids take a little time to degrade. I assume the 24 hrs. is for that.
The article makes it clear bactericide effectiveness is situation specific, and so may or may not work, depending on many factors. The principle looks sound though.
I sprayed a very low dose of copper yesterday, but I doubt it would be enough to help anything. More for just bac. spot control.
I got down to 23F, my buds are a little past first pink. Most look OK, some are dead. The pluots look worse. The peaches better. 32, 30, and 32 the next three nights after that no problems. I don’t plan to protect them though anymore.
Same here…i’m not covering anything now. I haven’t looked yet. I might take a couple of apricot flowers and see what they look like inside. Hopefully enough is there to make it worthwhile. I think the hybrid plums should be ok. We should be near 70F or more Thurs-Sunday… that should force everything into blooming.
Thanks Mark,
I read the whole thing, and like most “scientific” type studies, there
are so many variables involved, that the results are nebulous at best.
I sprayed KDL friday, because we had a freeze watch that turned into
a warning. Before I sprayed the first time, I irrigated all of my trees, as
was suggested by KDL. This study claims that irrigating helps in frost
prevention, but it also states that mulches and weed and cover crops
encourage frost formation. All of my trees are heavily mulched, and I’ve
kept the grass high, and I have no way of changing this. My main
problem last night, was that all of my stone fruit was way past shuck
split, and according to Clemson, there’s nothing you can really do to
prevent the fruit from freezing. Luckily, we obviously didn’t get down
below 33, which was our forecast, and I have minimal losses. So it looks
like I might get a decent crop and will get to eat some pluots for the
very first time. I believe last night was the last bad weather we’ll see.
I don’t know, if KDL worked or not, because my Santa Rosa, which I did
not spray, looks no worse than the trees that I did spray. Hopefully, I’m
not speaking too soon, and won’t have any delayed freeze damage.
I’m still glad that I sprayed KDL, because for me, doing something that
has a good chance of success, is better than doing nothing at all, and it
gave me some peace of mind. I didn’t get up in the middle of the night
worrying about what else can I do, and running around like a chicken
with its head cut off.
Good luck to all of you dealing with this freeze…
I have a physics question on the use of Kocide or the like for frost protection, it seems counter intuitive to me. I understand that bacteria can be the nucleus which causes water vapor to condense into dew or frost. They do that in cloud formation as well. The puzzling part for me I would think that good.
One can find many references to people putting a sprinkler on their fruit trees and the trees getting coated in ice which prevents frost damage. The water gives up its heat to the tree branch as it freezes.
I would think that the same mechanism would work with frost forming on branches. The water vapor in the air should give up some latent heat as it forms frost on the tree branches, providing some extra heat to the branch. If this is the case, then I would think having the bacteria to serve as nuc’s for frost formation would help protect against frost damage.
Yet Kocide is claiming the opposite. So assuming this has been tested, there must be something in the physics different that what I am thinking. Does anyone know what that is?
I recently finished my survey, most stuff is fine but pom and kiwi lost many shoots. I had one row of poms I covered but it didn’t help much. Figs also took yet more damage. Also there will be a very light apricot crop, three 27ish nights total plus lots of cold not helping pollination. This is my first year I have had a serious dent in my apricot crop.
My weather station alarm did go off early this morning but I didn’t hear it. Fortunately my wife did. It was in the next room and it should be by my bed to work. Anyway it was almost sunrise then so I did not do any blowtorching.
I’ll take a shot at that even though I haven’t really been following all that’s been said here. And I’m more into heat and tarp because that works every time if done right even for a much harder freeze than what’s claimed here.
My thinking is it’s not the surface ice/frost that important. That’s not what damages the fruit/buds/tree. It’s the internal ice, inside the fruit that causes the damage. The water in the fruit can and does super cool. Apparently it usually super cools to 28F because that usually causes no damage. If something causes that super cooled water to suddenly start freezing then the fruit is damaged as the expanding ice rips the cells apart. Apparently killing the surface bacteria cuts off one source of “freeze starter”.
In the past I thought they were talking about ice nucleating bacteria inside the tree or fruit. But don’t see how that could be if Kocide has any effect.
Just a conversation starter. Someone correct me if I’m wrong.
Most of my stuff looks okay but I noticed this on my flavor king just now. Looks like the leaves froze. How damaging is this?
That’s borderline serious. Losing the leaves isn’t that bad. But if it extends back into older wood it’s bad news.
Did it do that and not damage the fruit?
The tree had many blooms but I didn’t see any fruit set at all. That’s why I wasn’t worried about trying to cover it. My methley looks absolutely fine. Just the flavor king looks bad
Fair enough @fruitnut, but water doesn’t start expanding until around 20F or so, above that temp it is shrinking as to most liquids when they turn solid. That is not to say that even smaller ice might not cause issues in the plant tissues, lack of transport, freeze-dried type dehydration, etc.
But even so, the act of more water condensing from vapor on the outside of the plant should be transferring more latent heat to the plant, warming it up some. Unless of course the water vapor itself is cooled below freezing before it condenses out on the plant, in which case it may be cooling it some depending upon their relative temps.
There may be too many variables in play to make a blanket statement as to good or bad. But it just seemed to me that if there is a continuing supply of atmospheric water vapor which is above freezing (eg it’s raining or snowing) then that water should have some heat to give up to the plant when it condenses/freezes on it.
It may get more technical than that too, like does the added size of the frost layer increase the surface area of the twig enough to increase its heat loss over and above any heat gained from condensing/freezing water.
An interesting physics problem, I wonder if anyone has looked into the details.
Olpea
Thanks for the link. It helped with my understanding of ice nucleating bacteria. I’m going to talk to the researchers this year about the proper copper rate to kill the bacteria, but not the plant tissue. I will be more prepared for next year. Also going to get some info on how Promalin on apples for frost rescue would interact with the Apogee that I sprayed for help with fireblight. Looks like these 2 growth hormones might bang heads with each other.
I hit 27-28 in the apple orchard on my dual sensor min/max thermometer. 27 at 2 feet above the ground and 28 at 6 feet above the ground. Not sure about the temp at ground level, but the dog’s water bowl had ice about 1 inch thick. Temp in the peaches would have been in that same range.
The apples were close to petal fall, the peaches were at shuck split and the blueberry were also at petal fall. Just about the worst point in the bloom cycle for everything!
I’m not going to make any projections at this point, just wait and see how things develop over the next 2 weeks. With the freeze worry over I’m putting the control heads for the drip back together and running down the leaks. Hope to have the drip working on everything by tomorrow. If I don’t have fruit, I’m going to focus on growing plants!
Yipee. More thunderstorms with hail tonight. I’ve got some thumb size fruit now.
Blueberry,
I hope your peaches fared OK through the frosts. I think all of us are just about through this frosty weather. I suspected several weeks ago we wouldn’t be able to break out of this cold pattern. That’s generally the way it works. It’s almost never one frost event, but a pattern of successive frost events, which take their toll, each one more frustrating than the last.
We appear to have one more frost event here tomorrow night, then it looks all clear. I guess if there is anything left, it will sort itself out.
Steve,
That’s true. When water freezes, it gives off heat. When it melts, it draws in heat. The extreme energy from phase change is the whole premise behind how ice cream freezers work with rock salt. By lowering the point in which ice melts, it lowers the point of phase change, which means it absorbs a lot more heat at a lower temp, and freezes the ice cream much faster when the ice melts.
I understand your question, and I think it’s a good one. All the freezing ice crystals should warm up the blooms. However, remember most of the time there are multiple physics principles at work.
For irrigation for frost protection, the sprinklers run continuously. Experts warn damage will be worse if sprinklers are shut off before temps are well above freezing. I think the plants not only gain energy from the freezing of the water, but also because the running water has a lot of thermal energy itself.
I think this is different than frost from the air, which really has no supplemental energy source (a key ingredient, imo). I suspect the slow accumulated frost from the air is so slow it really doesn’t offer much heat to the blooms. But the main issue (according to the article) is that frost starts on the super cooled water on the outside and moves to the internal parts on the inside, rupturing the internal cells. Keeping the water super cool in a liquid state seems to avoid this issue.
I suspect if the frozen water stays close to 32 (like with frozen irrigated water running continuously) the natural “anti-freeze” inside the flowers (i.e. ovary, pollen tube, etc) will keep the internal parts from freezing. But if the freezing temps are well below 32, not enough heat is given off to keep cells from freezing.
That’s my thought anyway. But I really don’t know for sure. Great question, even if my hypothesis is off base.
Either way, I know frost is bad, unless one is continually watering, then frozen water is OK, although it can break branches.
