What do I do with my daisies?

TheGreenMan

I've got a leucanthemum Real Dream. I got it early spring and it flowered like a charm.

It stopped flowering mid August (we had cloudy and rainy weather for weeks) so I cut it  right back. 

It has now grown again.

Do I leave it or do I chop it right down at the end of Autumn or even next Spring? 

Your advice, as ever, is much appreciated.

This is it now:



This was it when in flower:

Fairygirl

They don't need any attention. Just leave it to die back for winter. 
It'll pretty much disappear, but you can remove dead stems if they're unsightly.

TheGreenMan

Thanks @Fairygirl I'm guessing the same applies to my catmints and achillea (I honestly can't remember what I did to them last year which suggests I did nothing!) 

Fairygirl

They thrive on fairly benign neglect @JamesS-B

Liriodendron

You can leave any herbaceous plant to its own devices over winter, and tidy them up before growth restarts in spring (though some things like Iris sibirica subside into a slimy mess and are best cut down in autumn, really).  Leaving stems & seed heads gives food for birds and homes for insects, and many things like achillea look lovely on a frosty morning...

TheGreenMan

@Fairygirl @Liriodendron Thanks both!  Benign neglect has seen me through thus far.  I think I'm trying to butt-in too much and overthink things.  I blame being here all the time while WFH.

Seems odd to be even thinking about things coming to the end of their season when it's 23 degrees outside.

Liriodendron

There's a lot to be said for benign neglect...