Protecting roots with bubblewrap

[RoadManDenDron]

I have seen people suggest wrapping pots in bubble wrap for insulation, our winters in UK are getting colder and although we don't usually see real cold until feb/March have been slightly below freezing -3c for a number of hours this week already. Our coldest temp last year was around -10c which is new territory for any of the experienced members in local clubs.

I bought some bubble wrap and it has now dawned on me, I have no idea what I'm doing with it!

is it ok if it covers drainage holes? should I cover top of the soil too?

Or do I simply wrap it round the outside of the pot leaving the top and bottom unwrapped?

Is it better to do this during the day when thawed or in the morning when frozen? As I understand it the freezing and thawing is an issue for the trees and the pots (-3c at night and 12c daytime today)

-10C = 14F
-3c = 26.6F
12C = 53.6F

 

[rockm]

FWIW, here in the eastern U.S., we regularly get temps like those you list. Have for years. All this depends on WHERE you are storing your trees and WHAT you're storing.

FWIW, I simply mulch everything into outdoor garden beds under shredded hardwood mulch and let them be. The mulch mostly remains moist enough to prevent roots from drying out and protects against the worst of the cold.

I would never use plastic to protect roots. It can complicate things tremendously, as it can interfere or even prevent moisture from getting to the roots. Would also, I think, encourage rodents looking for dry places to nest--mulch out under the elements is not as attractive.

 

[Paulpash]

I live in Yorkshire and it rarely hits -10C, usually a few around the -5C mark. Putting your trees in a heated greenhouse, by the house wall or on the ground creates a warmer micro climate.
The only trees I've lost to cold were in the bad freeze of 2010 when it dropped to a silly -15C for two weeks.
If you grow natives like Hawthorn, Field Maple, English Elm etc only temps lower than -10C will affect them. Stuff to be wary of are Tridents, Wisteria or some less hardy Olives.

 

[arbuscula]

I'm in Somerset, UK.

Spring of this year I put together a forest group using some airlayers from my Japanese maples. They are in a big pot which is heavy. They are on a display table stand about 5ft into the garden area. Last year I used the clear wheelie bin bags over to protect from those late frosts we had. I also use frost fleece protection over some trees and/or their pots.

*Regarding your question for bubble wrap*. Because of where the large pot is situated I have folded some bubble wrap up and wrapped it around the *sides* of the pot -secured the ends together where they meet. I have not placed the pot on top of the bubble wrap as that would stop any drainage of rain water... just wrapped the folded wrap around the side...

If/when we get low -3 to -4 degrees I will cover the trees over with the bags... doubled up if necessary. I lost some yew airlayers this spring and put it down to the late frosts we had and my not covering with the bags.