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Cutting back perennials and seed heads

CraighBCraighB Posts: 758
in Plants
Hi guys,

I have so many plants in my garden that I never deadheaded and they have all now got seed heads. I wanted to know what to do in regards to cutting them back to the ground and putting the dead material on the compost heap. If I do this will there be tons of seedlings appearing when I eventually spread the finished compost over boarders?

Thanks
Craigh

Posts

  • Mr. Vine EyeMr. Vine Eye Posts: 2,394
    Could you leave them now Craig until it warms up again in Spring? For the wildlife.

    That's what I'll be doing. I won't cut back anything that doesn't actually need cutting back. 

    RE compost - if you do hot composting where you turn it regularly then most of the seeds probably won't survive. If it's cold composted then you likely will get some seeds growing through, BUT, you can just hoe them off when they're little - still get all the benefits of the mulching regardless.

    You could always trim off the heads if you're concerned about it and compost the rest!
    East Yorkshire
  • FairygirlFairygirl Posts: 55,117
    Largely depends on the plants and your conditions re the compost bin and climate/temps. 
    It's a place where beautiful isn't enough of a word....



    I live in west central Scotland - not where that photo is...
  • Butterfly66Butterfly66 Posts: 970
    We left a lot of our seed heads on last year and it was a joy watching the birds eating the seeds over the winter. I then cut everything back in Spring and it all goes on the compost. As said whether you get seedlings or not will depend on what plants you have and as said how hot your compost gets. If I like a plant I don’t worry about seedheads going into the compost, Autumn or Spring.

    In our garden our experience of seedlings appearing is as follows - I know some of these are annuals/biennials - lots of seedlings popping up from the Verbena bonariensis, foxgloves, evening primrose, aquilegia, alchemilla mollis, sweet rocket, honesty, poppies and phaecelia

    I’ve not noticed any seedlings from my rudbeckia, helenium, echinacea, lupine, cosmos, hardy geraniums, crocosmia, perennial helianthus, astrantia, thalictrums. Only the odd sunflower seedling pops up. Our borders are very full so those not spotted may be ones who can’t cope with the level of competition.

    The only seedlings that pop up in noticeable numbers from our own compost are poppies, phaecelia and tomatoes.
     If you have a garden and a library, you have everything you need.”—Marcus Tullius Cicero
    East facing, top of a hill clay-loam, cultivated for centuries (7 years by me). Birmingham
  • CraighBCraighB Posts: 758
    Thanks for the advice. I will leave the seed heads for the birds as we do have lots of birds visiting our garden :)

    Then in spring next year put them on the compost heap. I do have quite a huge compost heap however there doesn't seem to be any heat even though there is a mixture of brown and green material. I'm not sure if it's too dry in the middle.
  • LynLyn Posts: 23,190
    Grass is good for getting the heap hot, do you keep it covered Craig,  wooden sides,  a piece of carpet and some galvanised sheets on top gets it going. 

    @Butterfly66. Out of your lists of nots,  I do get geranium and thalictrum popping up. 
    Gardening on the wild, windy west side of Dartmoor. 

  • PosyPosy Posts: 3,601
    In my garden wind and rain quickly flatten most old summer growth into a soggy mess, an excellent home for slugs, so I cut down anything that tends to collapse. I do get some seeds in my compost but nothing to worry about and some very happy accidental plantings.
  • CraighBCraighB Posts: 758
    Yea I do put plenty of grass on there and spread it around so it doesn't clump up and get soggy but I can't understand how it doesn't get hot.

    My old compost heap used to when I had one of them darlek compost bins and I put all the same things in it.
  • Butterfly66Butterfly66 Posts: 970
    Lyn said:
    Grass is good for getting the heap hot, do you keep it covered Craig,  wooden sides,  a piece of carpet and some galvanised sheets on top gets it going. 

    @Butterfly66. Out of your lists of nots,  I do get geranium and thalictrum popping up. 
    I’m hoping then that my thalictrums might self seed- fingers crossed
     If you have a garden and a library, you have everything you need.”—Marcus Tullius Cicero
    East facing, top of a hill clay-loam, cultivated for centuries (7 years by me). Birmingham
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