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Growing local

Our intention, with the soil in our yard is to build it up and let it take care of itself eventually in a natural way.   The wicking bins also need topping up annually.   We are tying to make things easier for ourselves as we get older.  The garden is almost full of permanent plants and only  our little decorative and supplemented veggie plants, need regular work.  We have delegated Tuesdays as our gardening day, spraying, composting etc.

 Well I have finally figured what the C:N figures are all about in compost books etc.  Our latest toy is an Aerobin 400.  We found that we had about 4 different composting heaps, which were not successful for us.  A hot compost heap, in my opinion, is the best system.

There are different recipes in different books and websites, and it can be very confusing. One website which made sense to me was HERE.  We placed our bin on  a concrete path not far from the back door and closeby the house, and we have put scrap bins for carbon- BROWNS and nitrogen- GREENS.  

So now I have managed to work out the recipe required for good compost, I can use all the stuff I have heaped around the yard.  It took us a whole day to 3/4 fill the bin, which has the capacity to carry up to 400kg of compost.  It should reach a temperature between 50 and 70 degrees. I have ordered a temperature probe to check on this.  Most weed seeds should be heated and killed but diseased plants etc will not be included.    

This heap should shrink within the next couple of days, so we will see how we go.  The 2 base doors, will allow us to access to the finished product.  As this is the start time of our compost heap, we will have to wait a couple of months for our first lot. From then, it will be ongoing. 

Most of us have our own adequate ways of handling our scraps, and I would love to hear them all. This Aerobin 400 is our answer now. 

TODAY is the 3rd day after filling the aerobin and I received the temperature probe in the mail today and tested the temp.  It reached 131 degrees F or 55 degrees C which is just over the active mark and into the hot area of the gauge.  The probe is 500mm long stainless steel with a gauge on top. 

Just read on Gardening Australia site

Question:- Can you compost all weeds?
Answer (JOSH:) You can compost anything organic, but to kill persistent weeds you need a really hot compost, about 65 degrees Celsius and above. Home composting systems rarely get that hot so weeds with rhizomes or bulbs, like couch grass or oxalis, are best put in the bin.

7 days since filling the compost  aerobin and temp reads 120F or 48.8 C which leaves it in the active stage and starting to cool down a bit.

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Replies to This Discussion

Good on you Christa & Ian, we love ours...

I hope that it works well for you Christa.

After trying this solution and that solution and being parted with many many dollars, I now use ordinary plastic rubbish bins with lids.

Pierce some holes using a hot poker (a metal kebab skewer) especially in the bottom. Sit the bins on the soil and layer them as and when. Poke a hole down the middle, add some Biodynamic prepared 500 and let them quietly mature for up to a year. Takes a while to make humus - the soft brown fluffy stuff in which all trace of the original materials has been lost. Mine have the added bonus of red compost worms who come into the bins from the soil and work their magic.

Hi Christa, my aunty has an Aerobin and swears by it! Glad you've found your composting fit :)

It's still confusing - 30:1 actually means 2:1?? 

Don't Make This Mistake: This ratio describes the chemical composition of a material and does not mean that you need a volume of brown materials that is thirty times greater than the amount of green matter! Don't make this mistake!

Generally 2:1 (greens to browns) seems to be acceptable. Depends on the density of the product also.

I just threw everything onto the pile and it all eventually broke down apart from actual branches. Cold compost though, not hot.

Lissa , It took me a while to realise that.  When an item states e.g. leaves 60:1 and food wastes 15:1 and fowl manure 7:1 - it means that that item has as in leaves about 50 parts carbon to 1 part nitrogen, and so forth.  It is the chemical compostition as you say. 

Basically my thoughts are browns decay slowly and greens decay rapidly.  

So branches, straw paper sawdust, mixed old manure  (browns) takes a while to decay by itself and  veg scraps, coffee grounds, green grass clippings (greens) decay faster.   This is due to the carbon nitrogen ratio.  

The last part of your comment varies in different books, online, etc whether to have 2 parts greens to 1 part browns or 2 parts browns to 1 part greens or equal parts green to brown.

This mixing ratio only contributes to the speed in which the breakdown happens.   Please correct me if I am wrong as this is important to me.  I don't want to handle compost heaps over and over again, not enough time in this life before I end up there. 

That is why I got an aerobin, it is an insulated compartment with a lung in it to keep it aerated and it is continually working through the layers where in 2 months the initial amount placed in the bottom is ready and the different stages of compost are going up the chamber with the freshest up the top. So you can help yourself to ready compost at the bottom doors when you need it.  Worms stay in the cool parts. 

No turning just adding to the top and wetting with water.  No rats or mice can get in. Dogs can't dig and try to eat the fresh veggie scraps.  

Roger I am happy that you have found a way to make your compost in an easy manner. Every BLF member will have found a way to suit their needs and it is good to share what we have learnt with other members, who are all different ages and have different strengths and needs.  

Maybe I am just come under the fussy category.

When the time comes for me to make compost again I hope I remember this conversation!

I cold compost using a couple of Gedye bins. These are open to the ground at the bottom. I don't try to hot compost due to the extra time and effort that this requires. Turning the heap every week or so is too much time spent in my busy life. I also don't want to try to balance the C/N ratio and moisture levels accurately, so I just add a layer of brown to the kitchen scraps every time I have a full bucket.    

This gives me a full bin every few months/ Yes there are lots of volunteer plants that come up when I use the compost but these are a bonus as far as I am concerned.

It was interesting to compare all the different compost samples at the last BOGI meeting. A lot of people must add lots of soil to their compost as many of the samples were very heavy. My compost is always quite light due it consisting of scrap residues and grass clippings or shredded mulch (e.g. woodchips). It also contains a lot more larger pieces than the obviously sifted samples on show. I found it very difficult to choose a best compost from the many on show. I could only go by smell, weight and feel.

Have a patch of nut grass that i tried to dig out but it seems to keep growing but the nuts and grass i dig up i put in a thermal cooker  after heating the pot on the stove  and leave till it cools next day and use it as mulch  seems to kill the nuts.If could set up a cooking system that worked off solar energy and added that to the compost would think that the boiling breaks down the green matter and open up for quicker decomposition  .The cooked material seems to disappear very quickly when placed around plants.

Sorry Jeff, I am having a bit of trouble understanding what you are saying about thermal treatment of nut grass. Maybe they do not compost well. 

One thing I was told about nut grass was, if when the nut grass comes up out of the ground and gets ready to make seeds, if you prune the green part as close to the ground as possible, you zap the goodness out of the nut.  If you keep doing it, you can weaken it.  I do this with isolated clumps that come up in the garden and then cover it with a brick or rock. So far so good, but it is also coming up all over the place and is a pain. We have a propane torch burner and often use that to keep weeds down, don't know if that would work with nut grass. 

The burner would work with nut grass, Christa as indeed did Roundup when I used it years ago. BUT and here's the rub: only the nut connected to the current green top is killed. Further nuts on the chain below ground will grow and put up a green spear to make more fuel for the whole plant. So you need to keep at it unless you are prepared to dig them all out. I did that but it was nearly 40 years ago and sitting on an upturned milk crate, digger in hand for hours at a time, is not something either of us could do now.

If i put the nut grass in the compost there would be a great risk of spreading the nuts or seeds  and how to treat the nut grass to stop it from growing could use water and place in a drum of water for a long time but that takes time could just put in the bin but i think nut grass has some good nutrients and cooking would kill the nut grass quickly and Sous-vide  would break it down .

  Sempra Nutgrass and Weed Killer  i see they use on sugar cane farms would think that sugar cane would be big enough to not be worried by nut grass but i think if not use weed killer every nut would regrow .

Its seems to be a challenge as far as weeds go Jeff.  If we ignore it, then it can take advantage and in our good well fed soil, it can be an eternal problem.   Where I see the nut grass growing and is very annoying, is in my paths between my garden plants and so I cover it with wet cardboard and then cover with mulch or wood chip to block out the light.  It works for a while.

In around and beside the plants, I trim the green leaf top off and throw that in the bin without the nut. I believe it makes a good manure tea, when strained.

Do you eat the nuts after their water bath? If so what do they taste like?

Our rubbish tips must be loaded with nuts from nutgrass.   Fortunately I have learnt to look at most weeds as friendly as some do grow quick and mine the soil and bring the nutrients to the top.  Chick weed is good for me, and I don't mind the occasional Sida retusa, they are long stemed and the food plant for the common eggfly butterfly.  I allow the odd milkweed as well for monarch butterflys but have to remember- cutting off the seed pod before they fly everywhere.   

Maybe as part of my experiment with aerobin, I should place a few nut grass segments into my bin and somehow tie them together or mark somehow and see what happens to them after some high temps. 


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