3 weeks and no comb, should I be worried?

[bozbee]

Added my supers just over 3 weeks ago. Checked them yesterday and nothing built on top of the starter comb. The bees are climbing all over it of course and I see them going in and out of the hive with yellow pollen on their hindlegs, but nothing. I admit that the coldspell killed all of the bloom and although we've had some pretty days the mornings have been quite cold. Thanks

[Kathyp]

what are they doing with the pollen?  what kind of foundation did you use?

[thomashton]

Are you feeding them? They need to be fed to stimulate comb building. If you just leave it to food they get from nature then you'll never get any honey for yourself this year and possibly they won't overwinter.

[Michael Bush]

Do you have an excluder?  Is there a nectar flow?

[Brian D. Bray]

I have 1 of my 4 packages doing the same thing.  They are foraging but not taking much syrup and seem to be setting one starter strips instead of building comb like the other hives.  I might have to break down and put frames with foundation in and reduce the hive size to a nuc to get them started.  I'm going into the hive again tomorrow and will make my discission on what I see then.

Meanwhile, the local beekeeper's meeting is tonight with a class on queen rearing on the agenda.  A definite must attend topic.