planting out broad beans

I made some tall pots out of newspaper, planted my seeds (Masterpiece Long Pod) and waited.  7 days later, half inch of stem appeared.  I was delighted, but one week on the stems are now 7/8 inches high!  I am concerned that it is too early to put them on the allotment?  Should I just move them to the cold greenhouse (only a little plastic greenhouse) to slow down the growth? 

At present they are in an unheated bedroom , sharing space with the chitting potatoes

Advice please!

 

Put them somewhere much cooler. Harden them off by putting them outside in a sheltered spot. Plant them when hardened, say next weekend. Plant them with a trowell so the soil is up to the lowest leaves as this will give the stem support.