Pinching out perennials?

[ErrolTheDragon]

I don't know why it's never occurred to me before, but looking at some of my overly-tall perennials flopping over despite their supports (michaelmas daisies at the moment but other things too), it's just dawned on me that maybe I should be pinching them out/chopping back at some point earlier in the year?

Do people do this, and if so which plants do you find particularly benefit from it and about when would you do it and how drastically? (Obviously different for each type). Clearly there are many perennials this wouldn't be appropriate for.

There’s the classic Chelsea Chop, when you cut stuff back in late may/early June, and the Hampton Hack variant for early July. The trouble is that you generally do this immediately after flowering; some things won’t get enough growth after that to flower that year.

The things I'm thinking of it'd definitely be well before flowering. I do cut back early flowering plants to get more flowers or at least fresh new foliage.

The Chelsea Chop is done before flowering

It stimulates side shoots. You get smaller flowers but more of them. Predictably, the further the plant has got towards flowering before you chop, the longer it will take to get to flowering, so it works well on late summer plants

Do you mean pinching the top leaves of new perennial seedlings? If so I’d do this now provided you leave two sets of true leaves beneath.

No, I mean some sort of pruning early in the year of established ones.

Which very evidently is A Thing....so... which plants do people most recommend chopping (wholly or partially) ?

The link I posted had a list of plants especially suited to it.

Yes, thanks for that! I was wondering what other people do irl

In that case, I would cut back now (while conditions are still frost free) any foliage which is getting too tall/floppy (e.g. with Japanese anemone or gaura) but leave the rest there as frost protection for new growth and cut back in the Spring. But it might depend on the plant. Sometimes new growth comes off the old growth in Spring.

Theres the phrase 'if it flowers before June, prune'. So you cut all the growth that's going over a bit and should get a 2nd flush. So I do hardy geraniums, alchemillia mollis, oxeye daisy's..don't bother with mexican daisies as they seem to just regenerate themselves without. Is this what you mean? I would leave them all now to go all dead and brown over winter anyway and then you chop away old growth in the spring...I think? Not an expert. I like to leave the foliage to break down as a bit of mulch and for insects etc.

I'm waiting for a proper frost to trim away peony foliage as I think you're meant to?

@Grandmasswagbag I think she’s talking more about the Chelsea Chop, a more recent technique, where in late May, before flowering (so it’s only useful for late flowering plants) you chop it back. This means the plant has to start again, but in a hurry, so instead of tall, liable to flop, stems you get much shorter stems. So neat bushy Michaelmas daisies instead of tall floppy ones.

Your rhyme is about stimulating a second flush of flowers later in the season. Although I think it might have originally applied to pruning of bushes, distinguishing between a) those that flower on this year’s growth, so you prune in spring, and it takes them a while to grow and then flower, so they flower late, and b) those that flower on last year’s growth, so you prune straight after flowering to stimulate that growth, and next year they’re ready to go, and flower early in the year.

Yes. I've clearly never paid attention when I've heard the 'Chelsea Chop' mentioned. I think I assumed it was some special method used to get plants flowering in time for the show rather than a useful technique that just happens to coincide with it and tuned out.😂

Yeah, it's called "Chelsea' because that's an easier way to remember when to do it - easier than thinking "was it May? or was it June?" and the newspaper coverage gives a prompt, almost as good as having it in your diary.

I wonder when the word "newspaper" will become obsolete? Or will it linger on like "pull the chain" or "dialling code" (now phones don't have dials).