Helianthus Lemon Queen?

I bought a Helianthus Lemon Queen about a year ago after seeing one in a garden I visited (at least that's what I thought it was). Mine is now just coming into flower. Only thing is it doesn't look quite like I was expecting - the flowers seem quite a bit larger, have more petals and are a brighter yellow. Just wondering whether I've been sold the wrong plant?

 

It's a Helianthus Kevin but I don't think it's Lemon Queen either, sorry.

 

Looks more like H. decapetala.

 

Agree it doesn't look like the Lemon Queen that I have. Mine is slightly paler and flowers are "tighter". Also mine have been flowering for a good 3 weeks or more so yours is very late to flower?

 

I have the same one which was sold as Helianthus 'Monarch', although apparently it isn't the true cultivar 'Monarch'. See the info on Bob Brown's page here: Cotswold Garden Flowers - Encyclopedia
It's the one described as 'Not Monarch', although the photo seem to have disappeared.

It's a nice plant, but it does spread quickly by long rhizomes and the clumps get very congested - good idea to dig up every few years in the early spring and replant a few bits to thin it out.

Worth getting 'Lemon Queen' as well if you have the space.

 

Thanks for the replies. I agree that it seems to be spreading very quickly - it is now swamping the Eupatorium and Asters that I have nearby. I think it might have to go because of this. Is Lemon Queen likely to be less invasive?

It's not the first time that I've been sold the wrong plant, I bought some Geranium White Ness last year that turned out to be pink!