Storing for Winter

[Alan F]

Just wondered if anyone had ever tried polystyrene chips to sink the pots in over Winter rather than sand. I send a lot of parcels out from web site sales and I'm always surprised how warm it is in the box of packing.

[ChrisB]

Never tried that, Alan, but sounds like quite a good idea for tender things.  Welcome to the forum!

[Anthony Darby]

The warmth you feel from polystyrene is the heat being reflected from your hand. It is a good insulator and will protect from frost, but a polystyrene box feels warm and a tin can feels cold when in reality they will both be at the same temperature.

[johnw]

Alan - I think these chips would allow too much air circulation around them. We successfully use wood chips (not as fine as sawdust) which we buy in 3 cu ft bales. Sand we find is mighty hard on clay pots.

I had once thought of a very thick sheet of styro with holes into which you could sink the pots. Sounded like a good idea until you think it through. The styro would block warmth coming up from the ground below and block conduction both ways. So there the pots would sit with nothing to do but freeze harder and harder with more & more cold penetration. Better to have a sheets of styro lining the interior of the frame and as a lid.

johnw

[gote]

It all depends upon how you do it. Anthony is perfectly right. You feel your own temperature.
In the winter, the cold comes from the above (or rather the heat disappears upwards.)
If a pot stands on insulation, it will follow the air temperature. A clear night without cover it might even get slightly colder than the air immediately above. (Because it will radiate heat into outer space)
The source of heat to the pot is the residual heat from the ground that is left over from the summer. The winter thermal situation is that the heat accumulated in the ground during the summer is dissipated upwards. If there is a cover of snow the heat will travel more quickly through the soil and more slowly through the snow so the bottom of the snow can be considerably warmer than the top.
A pot that stands on the soil will have some heat flowing in from the bottom and dissipate it both through the sides and the top so it will act as a cooling fin and have very little benefit from the heat flowing in from the bottom.
If it is surrounded by a medium that is insulating, it will not loose any heat through the sides but the area of the bottom where the heat comes in is smaller than the area at the topwhere the heat goes out. If it is surrounded by a not insulating medium, the medium will dissipate some of the heat it takes up between the pot bottoms to the sides of the pot so the pot is better off.
The water situation is of course an added complication. It can accumulate and perhaps freeze in the wrong place and suffocate the plant. Not so much a problem in a place where mean temperature keeps above freezing.
Yes i know it is confusing  
Göte
 

    
  

[Alan F]

Thank you for all those answers - and very technical they were too :-) Think I might be digging out my old beer brewing heat mats !!!

[Anthony Darby]

Wish I'd put heat collars used for brewing round the heads of my tree ferns back in sunny D.

[johnw]

"Better to have a sheets of styro lining the interior of the frame and as a lid."  Let me clarify my statement.  Göte is perfectly correct. I should have said "Better to have   sheets of styro lining the interior walls of the frame and as a lid".

johnw

[gote]

Thank you for all those answers - and very technical they were too :-) Think I might be digging out my old beer brewing heat mats !!!

I have no idea whet they are but it seems agood idea
Göte

[Anthony Darby]

My wife is not happy that I have "stored" Ponga the tortoise in one of the drawers of our fridge. It's the only place cold enough to hibernate her!

[ranunculus]

My wife is not happy that I have "stored" Ponga the tortoise in one of the drawers of our fridge. It's the only place cold enough to hibernate her!

Shell-by date?   

Hope it's a different drawer to the frozen pies!!!

[Alan F]

Gote:

http://www.homebrewing.org/Brew-Heat-Pad--Fermentation-Heat-Panel_p_1279.html

There you go - except mine are much older so not so fancy looking !!!

[David Nicholson]

My wife is not happy that I have "stored" Ponga the tortoise in one of the drawers of our fridge. It's the only place cold enough to hibernate her!

Shell-by date?   

Hope it's a different drawer to the frozen pies!!!

Might go down well with a drop of HP.

[Anthony Darby]

Not sure I should put up with your sauce David?

[ranunculus]

Not sure I should put up with your sauce David?

Oh, come on Anthony ... catch up ... !!!