[SPUDMIESTER]

I've just recently pricked out my first batch of tomato seedlings(tumbling tom) into 3" pots and are struggling for light on top of the fridge - would they be ok to go into my new recently erected greenhouse(not to plant) or is it still too cold?

[sunshineband]

It is still too cold in an unheated green house.
The plants would be better on a warm windowsill with a light reflector behind them made of aluminium foil. 

[Kristen]

I reckon on a minimum of 10C for Tomatoes. Probably May before I can be confident of that in my cold greenhouse.