What temperature for frost?

[Fezinio]

Hi all,

I know this may sound like a stupid question but at what temperature do you actually get frost in your garden/Lottie etc.

The reason I ask is because I just got a new min/max thermometer to put in one of my coldframes and it says that frost occurs about -20 degrees C or something like that.

Any thoughts?

Fez

[Snadger]

I always assumed that frost appeared at freezing point 32F or 0 Deg C ?

[Alice]

Frost

Hello Fezinio. Good question about frost. I think there must be some mix up about about the temperatures you quote from your thermometer. -20 degrees C would be a record most parts of this country have never seen (but you could be in the Cairngorms). -17C is the record for this part of the country and I hope never to see it again
The answer to your question is 0 degrees C is freezing point and you will get frost. Well that's according to the physicists. In reality you can get frost if the temperature falls below 4 degrees.

In short - under 4 degrees C, take precautions
0 degrees C, guaranteed.

Hope this helps.

[Fezinio]

Yeah me too lol

How very strange

[beefy]

Somethings not right Fez .Frost should appear around +1 deg or lower.
-20 is the temperature of frozen food in the supermarket freezers.Could the label be stuck on the thermometer incorrectly?

[Fezinio]

Thanks Alice and Snadger,

I think I need to look at the thermometer again. Knowing me I have read it totally wrong.

I would check now but all ready to settle for the evening and don't really want to tackle the cold in me shorts and t-shirt.

Roll and grow your own veg at 8.PM and before I forget come on you rip roaring potters (Stoke City FC) who play in the FA Cup tonight

[Nicos]

I agree...4 oC -expect to be nipped by frost.