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Composting and ferns

In a You Tube video about composting Monty clarified and simplified the whole business of what goes into the compost heap.
   The key, he said, was to mix 50% green stuff (as a good source of nitrogen) with 50% brown stuff - usually coarser stuff (for its 'carbon' content). For example: grass cuttings mixed with brown stems cut back from shrubs that had died back.
   That way, he said, the coarser brown cuttings would help allow oxygen get to the heap, thus preventing that horrible slimy matting that grass cuttings on their own can produce.

   My question is
: What about my ferns? They were very green until recently when they began dying back and became very brown. Are ferns a source of nitrogen or of carbon for the compost heap?


  • Blue OnionBlue Onion Posts: 2,488
    Can you shred them?  Or mow them over with a lawn mower?  That's what I do.. I pull stuff into the grass and run it over with the push mower.  Leaves, winter cut back from perennial flowers, etc.  Not wood, obviously, but my mower managed thick hollyhock stems just fine.  
    Utah, USA.
  • Birdy13Birdy13 Posts: 595
    Yes I could mow over them but it's not the cutting up that I'm asking about.

    It's about whether ferns are a source of carbon (usually the brown stuff according to Monty) for the compost heap or of nitrogen (the green stuff).

    I want to get the balance right in my new bigger heap when I start it off this year because my composting has failed in previous years when I didn't know this guideline of 50% green, 50% brown.

    The problem for me is that ferns look like a source of nitrogen while they are green but when they die back they and become brown. 
  • LynLyn DevonPosts: 16,759
    It’s not rocket science, just put them in, so if you get 48% of one and 52% of another, it really doesn’t matter.  During the winter I don’t have much green so it’s all cardboard, junk mail magazines envelopes etc, with some shrubs chipped up,  I can make up for that in the Spring. 
    Gardening on the wild, windy west side of Dartmoor. 

  • Blue OnionBlue Onion Posts: 2,488
    Literally.. follow the colors.  :)  If it's brown (or any other color than green), it's a brown.  Cardboard, paper towels, nut shells, tea bags, egg cartons, brown ferns, brown grass, brown stems, brown weeds, etc.  If it's currently green (or recently alive), it's a green (meaning it has much more water in the cells).. green grass, green ferns, green stems, veg peelings, green weeds, etc.  
    It all depends on your composter, your location, and the time of year.  50/50 is a good rule, but I live in an arid high altitude desert.. my compost is always dry, even thought it is about 90% "greens".  If you have a covered compost, and it's the middle of a summer heatwave, you could do fine with a 20/80 in favor of the "greens".  If you have an open top compost heap, you may need a 20/80 in favor of the "browns" in the middle of a wet winter.  There is no perfect science.. just a bit of logic.

    Back to your question (and it's a good one, I remember wondering the same thing myself when I started composting):  Brown ferns are a brown.  Shred them and keep them at hand to mix in with your greens as you put them in.  50/50 is great, if you have it.  Then you can adjust with water if it's too dry in the summer.  
    Utah, USA.
  • Birdy13Birdy13 Posts: 595
    Thanks for your answers, both.
       I'm not over worried about getting it exactly right, Lyn, although the question may have seemed a bit fussy. I am always interested about the science behind the simplified explanations expert gardeners give.
       When I considered my ferns in the light of Monty Don's You Tube video on composting it led me to wonder whether the nitrogen content of green plants diminishes as they grow brown and whether the carbon content eventually outweighs by ratio any residual nitrogenous matter.
       I also wondered whether the manner in which ferns die back and regenerate so reliably and have done since prehistoric times is connected to them having a perfect chemical balance within their structure for creating their own specially designed compost.
       The exact nitrogen/ carbon balance not a particularly big issue for me, just an intriguing scientific question that interested me.
       Thanks for your input Lyn and Blue Onion.
  • FireFire LondonPosts: 7,319
    I would agree that they are both - like grass. When they are fresh they count as 'green'. When they are totally dead, they count as 'brown'. Both states offer different things.
  • Can I invade this thread a little and ask about the ''Browns"? I'm actually currently building a larger compost box for my garden and was wondering if these class as browns: -

    * Filtered coffee AND the Filter (even though the filter is white?)
    *Amazon cardboard boxes (obviously without the sticky tape on)

    I really want to increase the brown within my compost as it really is mainly green but I'm not too sure what consumer items are classed as brown and safe to throw in. 
  • fidgetbonesfidgetbones Posts: 14,808
    Coffee grounds, paper filters, newspapers, and corrugated cardboard are all brown. Tear paper,and cardboard into strips, and wet before adding unless you have a lot of grass cuttings to balance it.
    You don't stop doing new things because you get old, you get old because you stop doing new things. <3
  • punkdocpunkdoc Sheffield, Derbyshire border.Posts: 8,674
    White, as in paper, counts as brown!
    Walk out to winter, swear I'll be there.
    Chill will wake you, high and dry
    You'll wonder why.
  • Hostafan1Hostafan1 Posts: 26,166
    Personally , I take everything MD says with a large pinch of salt.
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