Rescuing a Dying Cork Bark Pine

[Dav4]

I should have posted this in my previous post, but the reason I like the overwintering trees to be in frozen soil is that they don't need to be watered. I simply placed snow over the pots when available and it melted to supply water as needed to the trees. I agree with others that it doesn't have to stay frozen to remain dormant- temperatures consistently under 40 F will maintain dormancy. I just think it's easier...

 

[Paradox]

I prefer to put my trees in my unheated, uninsulated garage for the winter. I dont have a good place outside to put them where they would be secure and we dont get snow consistently enough to use Dave's method. In this situation, you still need to monitor frequently.

In the winter, I check my trees every couple of days. Sometimes I need to water them once a week, sometimes some of them can go longer, sometimes a few need to be watered sooner. It changes as temperatures and conditions change. There is no set formula for when they need watering so I cant tell you one week, two weeks, 3 days. You are just going to have to watch them and act accordingly. Youll figure it out, it is not rocket science.

It usually doesnt get to the point where the soil freezes in there. I keep a bucket of water in the garage with a cup to water trees when they need it. It gives me something to do on the weekend during the long winter.

My method is more labor intensive than Dave's method, but I prefer keeping a closer eye on my trees than he needs to.

 

[sikadelic]

Thanks. I guess I'm a bit paranoid as I have been here the whole time I have had my trees. I would hate to lose them due to inexperience.

 

[Catalyst05]

Continuing on with wintering advice in the garage idea, when is light advisable?

Lets say I had a garage that I was able to keep at 38 degrees F and I was wintering Japanese Black Pines. If I were able to provide sunlight, or had some strong grow lights, would that be recommended? If so, how many hours of strong light do you think would be advisable?

I have talked to people who strongly believe in providing light for pines during winter. I have also heard from some, and from youtubing Peter Warren, that you can push a black pine during winter with the addition of grow lights (to keep the roots growing). Anyone have any experience with it?

 

[Dav4]

Dormant pines don't need light so keeping in a poorly lit garage shouldn't be an issue. However, the warmer the winter ambient temperatures are, the more metabolically active an evergreen like a pine becomes. 38 F is, in my opinion, too warm to keep a pine fully dormant, and I would probably want to give trees in that situation supplemental light for at least 8-10 hours a day. Again, one of the reasons I liked my garaged evergreens to be in frozen pots was because the lack of light was never an issue. Once the soil thawed and the temps inside the garage were in the 40 and low 50's during the day, it was time to move them outside.

 

[Catalyst05]

So is it safe to winter Japanese Black Pines at 38 degrees F with 8-10 hours of light, for prolonged periods? Does this meet the dormancy requirements for the tree? What if I was able to keep the trees a little warmer, say 45 degrees consistently?

The reason I ask is because I'm from Wisconsin, and it's almost a given that winter (at or well belong 32 degrees F) will be around five months long. I fear if I keep them at 38 degrees for five months with no light in a garage I will have some losses.

 

[Dav4]

So is it safe to winter Japanese Black Pines at 38 degrees F with 8-10 hours of light, for prolonged periods? Does this meet the dormancy requirements for the tree? What if I was able to keep the trees a little warmer, say 45 degrees consistently?

The reason I ask is because I'm from Wisconsin, and it's almost a given that winter (at or well belong 32 degrees F) will be around five months long. I fear if I keep them at 38 degrees for five months with no light in a garage I will have some losses.

I know that JBP grow far down into FL where it may only fall into the 30's a few times every winter, so I'd bet it would meet their dormancy requirements. The real question is asking whether this is the best way to over winter JBP in your location. I know there are members here who live in the upper mid west into MN and may grow JBP. You should start a thread on the subject and hopefully get responses from folks who live in a climate such as yours. Good luck.

 

[junmilo]

I have attached photos of the cork bark jbp in question. The color difference of the needles is due to lighting when I took them...what do u guys think?

 

[Brian Van Fleet]

I still think it dried out over the winter. The new growth looks good, and it appears to be recovering. I'd still cut off the dead needles, avoid moving it at all, water sparingly, feed, and full sun.