I would also like some advice as mine never flowered.
As they are a member of the rose family and my roses haven't performed fantastically I would suggest the weather.
Also there is the grizzled skipper (butterfly) that could havehad something to do with it
i also had not one flower on mine.. so must be weather.
Which Geums are we talking about? My Mrs J Bradshaw and Totally Tangerine (I don't know the grown up name I'm afraid ) flowered for ages this year, Mrs Bradshaw is still going now although I'm hoping she'll set seeds.
I have two un-named much smaller Geums with little orange flowers on that haven't done at all well this year though.
It could be Pennine, I've just had a look around the internet but there doesn't seem to be much information about them online.
You could ask here http://www.geumcollection.co.uk/index.html by using this query form http://www.geumcollection.co.uk/feedback.html
I'm a big fan of geums too and think they are a much over looked little plant.
My sister in law keeps pulling them up as weeds, when she has done nothing about the dreaded himalyan balsam creeping in to the bottom of her garden.
There is one which is a dreadful weed, Geum urbanum. I would say that all ours have flowered their little cotton socks off. G. Blazing Sunset has been magnificent all Summer. Keep cutting it down and it throws up more flowering stems.
The Geum rivularis types do better in a more shady position or in damper soil if in sun.
Not got Totally Tangerine......yet. Refuse to pay £9.99 for it or even lass willing to pay £12.99 for it which is what I saw it priced at in a Wyevale.
Had a little count up only got 28 of them.
I have grown mine from seed, sown in 2011, so I do not know the variety. I will try moving them into the shade.