Sunflower or Artichoke?

Hi all, I got some 'roots' off freecycle earlier this year and potted them up, all the lady could say was that they were tall yellow flowers. Now they have flowers I can't decide whether it's a form of perennial sunflower or jerusalem artichoke?; or maybe even something else?

Any ideas?

Thanks

 

Are they about 5' tall?

If so they look very much like a large yellow daisy type flower I "acquired" (with permission) from a Pub garden a gew years ago. They fill attractively a corner of my garden, benefit 3 neighbours and are loved by bees.
In winter they die back and I cut to ground level. They also spread, so you can share.
I think you've done well.

 

Hi, thanks for the reply, as I wasn't sure what they were I potted them up in 3lt pots, so their growth has been restricted I suspect, but they are still 3-4ft tall and they are spreading in the pot with new shoots popping up..:thumb:

 

My flowers are just coming out up here, but they last into October.
Generally they are great value and the colour is intense.

 

I've given that stuff away on freecycle as well. I think it's a type of perennial helianthus. Flowers for several months, doesn't need staking, fills a space fast. A very useful plant. Some of my friends who I've given it to complain it's too invasive but I have not found it too difficult to dig out the thick roots or pull out a stray shoot where it's not wanted. You can chop it back around the edges in spring but I find it does even better and flowers longer if it's dug up and moved around, using the fresh shoots from the edge pf the clump.

 

I'm thinking it might just be some kind of Silphium, possibly.

 

Thanks for the reply Pete, the plot thickens , just googled Silphium and it looks like some of those too.....

 

I see from the pictures in the site below that the leaves do not seem to be similar to yours so it is probably not jerusalem artichoke...



Topinambur - jerusalem artichoke - Willkommen auf pflanzenliebe.de bei den essbaren Pflanzen!