green -> brown?

Presently using grass clippings as mulch, and noticing that the clippings go dry and brown after a while. Could they then go in compost bin as a brown layer?

 

Yep, the more layers of assorted stuff the better, cardboard crumpled up between layers of kitchen waste helps too

 

Thanks

 

Are you asking if grass is classed as brown 'carbon' once it has dried? If you are I would've said no. Am I wrong? It feels as if my world is about to be shaken to it's very core if so.

 

While we're on the subject, is packaging made from corn starch classed as green or brown?

 

Hi nFrost, my question stems from conscious ignorance, which I hope will leave your world unrocked. I wondered if grass's use as mulch would render it inert / otherwise unsuitable for composting. Seems like it wouldn't... but I'm wrong a lot.

 

I'm wary of using fresh green grass cuttings as a mulch - they can heat up quite quickly and I worry they will "burn" my plants

 

I'm afraid so

After water, the most abundant ingredient of plant cells (including grass) is carbon. While its green, it is still also loaded with nitrogen too but the nitrogen is much more volatile than the carbon, and dissipates quite quickly through various natural processes. The carbon largely stays put, so once the grass has been allowed to dry, exposed to air and microbes and sunlight etc, it becomes much more carbon than nitrogen, so it is a 'brown'.

In theory, the same processes would happen in the compost bin, as the microbes will still unlock the nitrogen just the same, but its all about a balanced diet. Too much nitrogen in one go upsets that balance, so the good bacteria doesn't thrive.

Also, the high water content of freshly cut grass leads to anaerobic digestion, which is where the naughty bacteria comes into play, and it gets all stinky.

 

I've been spreading the clippings out to dry them before using them for mulch. Haven't had dry enough weather to do that lately, and the grass is overdue for mowing, too. Been eyeing the dead bracken out behind the house, some say that's good mulch as well... but I hear we shouldn't take anything out of the woods.

 

Keep eyeing it, but not for a mulch. Just be ready with the round up if it gets too close. Bracken is horrible stuff, and a nightmare to get rid of.

I can think of three reasons not to use it as a mulch:
* It will turn the soil slightly acid. Ok if you want to grow acid loving plants, but generally not the best thing.
* If there's any spores on it, you'll end up with a lovely bracken garden (and pretty much nothing else)
* When bracken stems dry out, they become very brittle and sharp. As sharp as broken glass in fact, only when it cuts you, for some reason (maybe dust on it, maybe the chemicals in it, I don't know) it hurts more than it out to. Imagine a paper cut, multiplied by 1000.

A potential fourth reason is that bracken contains carcinogenic compounds. Its mostly the spores that's the problem, but I wouldn't trust any part of it really.

That said, I made a load of compost out of bracken a few years ago, and will do again, but I did it on my piece of land, which is bracken infested anyway, and didn't bring the compost home until it was not longer recognisable as bracken.

 

Thanks for that Clueless, my world has indeed been rocked. Fresh grass cuttings in my compost bin go brown/yellow in a few days. Also steaming a fair bit so must be fairly happy.

 

If I remember correctly the one day I listen in biology at school, nitrogen (in its mineral state) is combined with carbon to make proteins, but you need more carbon atoms than nitrogen to form the chain of, erm, thingies, that make a protein. If there's too much nitrogen, it becomes toxic to the good bacteria, I think. I do wish I'd listened more.

 

Presumably your shreaded paper has ink on it? I know its there in your composter in quite low concentrations but it sounds a bit iffy to me. Ink containing synthetic dyes and or pigments. What do you think please?

 

I wouldn't bat an eyelid. We all get vastly more poison just breathing the air in the street.