Do I deadhead Echinacea?

[IHopeYouStepOnALegoPiece]

They have like a cone in the middle, the petals have all started to drop off, do I deadhead them for more flowers or are they done and dusted?

(I’m new to this gardening lark if that wasn’t apparent )

They do produce more flowers (you might already see the buds in the axils where the leaf joins the stem), so I usually dead head once the "cone" no longer looks attractive (I have a pink one with orange centre, and the orange centres are quite striking for a long while after the "petals" have fallen).

Actually, what you are calling "petals" are in fact ray florets - if you look with a magnifying glass you'll find they have the sexual parts of the flower inside, so that each "petal" is a complete flower. The coloured bits in the "cone" are also complete flowers, so that what we think of as a "flower" is in fact an inflorescence of dozens of flowers.

Thank you! That’s really interesting!

Can I also ask, whilst I have an expert here, my sweet peas have gone yellow and aren’t producing any new flowers at all. Have I ruined them somehow or have they just come to the end of their life??

my sweet peas have gone yellow and aren’t producing any new flowers at all. If they've been going for quite a while, they might just be coming to the end of their life. Mine are dying off now. But mine turn to straw, rather than turning yellow - I grow mine in tubs. Are yours in a tub or are they in the ground?

There in a tub but they’re definitely straw like so I think they’re probably dying off!

Thank you

Sweet Peas need continual picking and dead heading in order to last throughout the summer. Otherwise they die off, thinking their reproductive job is done.
I also cut off the tendrils, as they are a waste of the plant’s energy, they are thirsty plants and nee a lot of watering.
I have learnt this over many years of short lived sweet peas, mine fortunately are still going strong, but I fear will only have a couple of weeks left in them.