The final instalment from our guest blogger Jim Buckland: composting for the future
Until recently we used all of our compost in new developments where it was used as a soil ameliorant and thus often had at least a six month period after being spread and before being planted into. This had two advantages. Firstly we could use a stale seed bed technique and spray out any weed seed that germinated in our less-than- fully-pasteurised product and secondly it offered an opportunity for further breakdown in the soil. We have now just about exhausted those possibilities for new developments and so the compost is now mainly being used as surface mulch.
What have we learnt from doing this for a decade?
Firstly, a shredder is best for dealing with green but not seriously woody material. For the past few years we have chipped all fully woody material above ½inch diameter and our end product has been better for it. If you had sufficient space to allow your heaps to mature for a couple of years this may not be such an issue but we don’t, so it is!
Secondly, regular turning is a must to achieve high, even temperatures throughout the heap. It is these that will pasteurise your heap and prevent it being a weed infested fifth column that you introduce to your beds every time you spread it.
Thirdly, maturation is important i.e. letting the heap stand for a further period after that early thermophilic stage.
Lastly, it’s vital to mix all grass clippings through the pre-shred pile to ensure they are shredded which doesn’t happen if they are just stuck on top of the post-shredding pile. This has stopped the problem of great slimy, anaerobic blobs of material turning up in the supposedly finished product.
In addition to this process we also generate large quantities of hay from our wild flower meadows. This is partly pre-shredded because it has been through an Amazone flail mower and is thus fairly pulverised before it hits the heap. To deal with all this we have created another two yards, one at the end of the garden and one in the Arboretum where the material is stockpiled in two huge heaps. These are turned three or four times during a year and are pretty well ready to use as a compost or mulch after 12 months.
Finally, as previously mentioned, we have a large chipper to deal with all the woody material we generate. This produces a pretty consistent chip about ½inch square. Again the chips are stockpiled in two heaps alongside the hay piles. These are turned once or twice over a twelve month period and are used primarily as mulch.
To conclude - this is not a cheap exercise; however in an ever greener world it is one that is both morally and environmentally correct. And for myself? Despite a more world weary view than that of my 16 year old adolescent self I have retained my passion for the age old practice of composting and nurturing our greatest legacy, the soil that sustains us all. Happy composting!
Happy composting indeed Jim and a huge thank you; impassioned and gripping your blogs have reinvigorated my own passion for composting. No wonder the West Dean gardens are so spectacular and I certainly plan another visit soon – Annie.