Begonia Plug Plants

I planted some Begonia plug plants a month ago and they have shown absolutely no sign of growing. I am getting really fed up with it now as this is the second lot of plug plants I have tried with no luck. They are the Begonia Illuminating variety and are supposed to bloom in apricot and gold colours. Any advice on how to get these going or am I flogging a dead horse?

 

There's another thread on the same subject here.

 

I think that this year being such a bad summer you are indeed flogging a dead horse!!

Val