Mike McGrath on TED talks, Everything …Composting

Anne Arundel,, MD(Zone 7b)

Just starting to watch but would expect it to be good

Enterprise, AL(Zone 8b)

I watched the video, I did find it entertaining but disagreed with some of the things that were said. I compost truck loads of leaves every year, when I have grass clippings I mix them In with the leaves when I have kitchen scraps I mix them in also. In the video he states that kitchen scraps do not turn into compost only the leaves do, that the kitchen scraps have no nitrogen in them and do not heat up, that is what I heard: If I am wrong in that correct me. The kitchen scraps do turn into compost and do heat up the pile, so I assume they have nitrogen in them. He seems to think that you should not mix kitchen scrapes in with the leaves, but I fail to understand the reasoning. I think they actually help to draw in the worms that help the leaves decompose even faster and become more enriched. This is so against everything I have read, and experienced that I am thinking maybe I missed something. Let me know what you think?

Silver Spring, MD(Zone 7a)

I found this confusing. Why are food scraps "cold?" Aren't they full of nitrogen?

Anne Arundel,, MD(Zone 7b)

I think he went a bit extreme in some ways in order to make it more 'entertaining' , just as many things in media need to make a different 'statement' in order for anybody to pay attention.

Kitchen scraps do have some nitrogen. But remember that vegetable peels for example would have a LOT of water in them so by weight, they aren't giving as much nitrogen as one might want to think. I did heat up a leaf pile once by adding 2 -3 large fruit crates worth of fruit and vegetable discards from the organic market all at once. . And if you can get heat going at all in cold weather, i feel like you're getting a step up.

I liked most that he emphasized how valuable fall leaves are and ' stop throwing them in the dump.'

Enterprise, AL(Zone 8b)

Yes, I agree it was fairly entertaining, but it would have been much more so to me with the facts. I also watched one of the videos that was listed adjacent to this one, it was about composting food wastes on a commercial level. It was not just the part about food wastes not having nitrogen and being "cold" , it was the part about kitchen wastes not turning into compost, "only the leaves". That really freaked me out!
But I also did like the way he stressed the importance of leaves, I love collecting leaves, my wife does not appreciate it much so I had her listen to part of the video, it did not change her mind. He answered the question about being able to grow plants in pure compost "leaf mold", but because he was wrong on several of the facts " in my opinion" I am not able to put much faith in his answer of "yes". He also said that you do not need to add anything to the leaf mold, from my own experience I question that statement also, but I have to scientific evidence to prove it. It just seems my plants do better with nitrogen added when I use all leaf mold.

Silver Spring, MD(Zone 7a)

l collected a ton of oak leaves last fall and tried to make leaf mold. I also had my regular compost bin with leaves plus grass clippings/food scraps added.

I got compost from the mix of leaves and nitrogen, but the pile of leaves didn't break down at all after 12 months. They actually look perfectly preserved!

Seedfork, I think there actually is scientific evidence for leaf mold being different from compost that you get from mixing nitrogen and carbon.

Enterprise, AL(Zone 8b)

One thing I certainly agree with in the video is the part about shredding your leaves. I use my lawn mower. I had several piles of leaves and grass clippings mixed with what few kitchen wastes we have mixed in, I had one pile of pure shredded leaves, and they all made beautiful finished compost. I try to shred all the leaves I collect (that is many truck loads, and yes it is a lot of work) the rate of decomposition is so much faster that way. I am sure the final product would look the same if time were not limited. Maybe two to three years for a finished pile of un-shredded leaves compared to six to eight months for shredded leaves. Now, you could use the leaves much earlier than that but it seems to take at least six months for my leaves to actually look more like soil than leaves.
Now I know leaves don't have a lot of nitrogen in them, but a shredded pile of leaves that is kept damp will definitely heat up without adding anything to them. I know I live in Alabama where winter is not that cold, but my leaf pile will be smoking hot after a few days, and that is just pure shredded leaves. But by adding kitchen wastes and grass clippings (I think they are both close in their nitrogen content ratio) the pile will heat much faster and reach up to 160 deg. I have read debates on rather "hot" or "cold" composting is best, but I think they are both good. If you need compost in a hurry use the hot method, if you don't need it in a hurry, or don't have the energy or time to work the piles us the slow cold methods.

Silver Spring, MD(Zone 7a)

Seedfork, only about half of the leaves were shredded. I simply ran out of energy after awhile. :) But I think you're right, especially with oak leaves, that they decompose faster when shredded.

Everett, WA(Zone 8a)

>> The kitchen scraps do turn into compost and do heat up the pile, so I assume they have nitrogen in them.

Seedfork and sallyg, I agree with you. Kitchen scraps and fruit-stand dumpster-diving-treasure (rotten fruit) are great for adding N to a compost heap. Along with coffee grounds, those are my main "greens".

ssgardener, I think that oak leaves are very tough compared to other leaves. Comparable to Rhododendron leaves. One friend "ages" oak leaves for a year before turning them under his garden (whole). You can still see parts of them a year later!

I agree with everyone who says that shredding leaves speeds up composting. That is extra-true for oak leaves and truer yet (truest?) for tough stems and anything woody.

I keep meaning to resharpen my lawnmower blade and shred everything woody FINELY before composting it. If I chopped everything small enough to be a soil component, I would not have to screen my compost before using it!

Thumbnail by RickCorey_WA Thumbnail by RickCorey_WA Thumbnail by RickCorey_WA Thumbnail by RickCorey_WA
Baltimore, MD(Zone 7a)

OK! I just looked at--and listened to--Mike M. and his long, repetitive talk
about composting leaves....

I have been doing it for years and years! BUT--and there is a BIG BUT.....
I do not have an open compost pile. I have an aging, cracked, useless
"Earth Machine". I call it my SEM--(Stupid Earth Machine) and Sally knows all about this.
It is cold---it never gets mixed--can't do it through that opening on top, as you cannot
do the old Heave-Ho and turn the compost over.
First time I tried--I cracked the lip of the container as I was trying to use it as leverage.

It has been 4 years since I emptied it--but it must be working--as it has never overflowed
with all the endless Kitchen Veggie scraps I dump in there. I go through a LOT of these.
The level just slowly sinks....

I won't go through a long story about what it takes to get to the "black Gold" below--
but i can tel you it is NOT via the little drawer at the bottom. That is a joke!!
Because to get to the "good stuff", I have to dismantle the whole thing, take it
apart and divide up the composted part with the not-yet-composted part,
which gets put back in the SEM. Re-assemble the SEM and continue dumping
piles and piles of veggie scraps in there. occasionally, I put some leaves in there--
but it does not have room for more than a bucket-full.

Leaves. Yes! I use my faithful Toro Shreder/Vac to shred all the raked up leaves.
Two shoulder bags full make one 33gal trash bag full.
I add some water to it (if the leaves are totally dry) and a handful of some kind of high N
fertilizer. This year--I used dried blood--and am kicking myself for not using some of
the coffee grinds of which I have a 5gal bucket-full just sitting there....
These bags contain NO food scraps--just leaves. Mostly maple leaves.
I put the filled black bags under some shrubs and wait...and wait....and wait....
In about 2 years time--I have some presentable leaf compost.
But--by then,the black trash bags themselves are quite brittle and composting...

I have been wishing for years to have an open 4'x4'x4' open compost bin.
Haven't found anyone to build it for me. Yes! I know...there are easy ways to do it--
but i am an old geezer and not that handy.

Here is my S.E.M. sitting there in all its glory...in 2008. It looks much worse now.
Full of all good things, a zillion pill bugs and larva doing their thing in there...
What a zoo in there in hot weather! Lots of worms too-but mostly at the bottom.

These SEM's are sold by the truck-load on mall parking lots with all kinds of promises.
I fell for it too--any years ago. Need something better....

Thanks for listening----Gita

Thumbnail by Gitagal
Everett, WA(Zone 8a)


I agree with you that coffee grounds are GREAT for a compost heap. They are high in N and already finely ground up.

>> I have been wishing for years to have an open 4'x4'x4' open compost bin.

I forget if I've asked you before: why not just make a compost pile on the ground?

That seems to me like the best way, since it lets excess water drain out, and lets worms and soil insects crawl in (or out, if it heats up too much).

Since you already shred your leaves, they shouldn't blow around.

Baltimore, MD(Zone 7a)


We have talked way back on this topic---I believe....
I cannot have an open pile of compost as I live in a development.
My property is small (65'x100') and surrounded by other houses.
People here take care of their lawns and garden. SO--no pile of stuff anywhere...

The other problem would be that I have 2 BIG Maples in y back yard
and their roots find a way into everything in a matter of one year.
IF I had a compost pile--it would be full of roots in no time flat.

I have A small area saved to, hopefully, build this 4x4x4 open compost bin.
Look to the right of the raised bed. Right now--it is just a walk-through to my
neighbor's yard. It also has massive tree roots, above ground, in that area.
Any compost pile I would have there, would have to be elevated slightly
so the roots cannot grow upward. Will deal with that idea when the time comes--
IF it ever happens...

Here is the spot....look to the right of the newly built, raised bed, which, by now,
is also full of maple roots. And i was hoping that this would be my veggie bed......
I almost hate my trees for that!!! But--I love them too--for the shade they give me
in the hot summers...It is 1-* cooler to just walk into my back yard...

Here is my whole back yard--left...center..and right....Open are just to the right
of the patio light bulb.
Pic. #4---The area saved for the future compost bin---(this is from 2011)


Thumbnail by Gitagal Thumbnail by Gitagal Thumbnail by Gitagal Thumbnail by Gitagal
Brooksville, FL(Zone 9a)


Wow I love your backyard. not to big and it doesn't look to small, but then I'm not the one living there. Funny that your neighbor to the side there has a privacy fence up and non of the others do..LOL


Baltimore, MD(Zone 7a)


The neighbor's to the right put up that 6' fence all around their whole back yard.
Of course--one side of it now also fences off MY yard!
I was very upset about this, but in about a week, i decided it does not look so bad
as a backdrop along my corner bed.

They are from Pakistan--and I understand that that is how they garden
back there. Sometimes--their fences can be 10' tall...

We are neighbors--so peace is best.....Gita

Brooksville, FL(Zone 9a)


When we lived up north we had the most incredible tree park back yard and you could see through to each others yard, kinda good as you could pick up tips from what others were doing and kinda bad in that others might use your designs...LOL then one puts up a privacy fence and just destroyed the view through the yards... but after a while we all got use to it. It doesn't look bad in your yard, just kinda pops up when the other areas are clear.

My sister use to live in Baltimore, don't remember where now, it has been more than 30+ years ago, but it was a pain having to drive from Alexandria, VA to Baltimore, way too long of a trip....

Stay warm and safe.


Everett, WA(Zone 8a)

I forgot! Neighbors and tree roots.

Since then, I also ran afoul of tree roots. A pine tree (or some other evergreen) near my compost heap discovered it, sent roots into it, and devoured it. So I moved it. (The heap, not the tree.)

Thanks for reminding me that I had better spread the compost from that heap before the bushes' roots get to it.

Post a Reply to this Thread

Please or sign up to post.