New 50:50 compost heap 160901

New heap instigated, roughly:

  • 50% grass and clover with some nettles and comfrey
  • 50% wood chippings.

Approx 15% N but estimated from the grass clover mix at about 50% grass, roughly equal mix that and green leafy (including relatively high nitrogen comfrey and nettles) and woodchip.

This was seeded with (very small!) soil samples from Staverton Thicks, Rendlesham forest and Captain’s Wood, all old, well established woodlands. We did this in the hope of introducing a wide soil food web to our heap, and subsequently to the soil. When we looked at these soil sample from the woodlands under the microscope they were certainly far richer in soil life than the soil at The Oak Tree at the time!

shredded evergreen shrub leaves

So the heap was made up of :

  • 30% green leafy shredded conifer leaves
  • 30% grass, clover nettles & comfrey
  • 40% woodchip
Shredded conifer foreground and grass and clover background

Good initial progress but this was not sustained. Perhaps this should have been turned on the first Monday, rather than the Tuesday

Compost heap temperature profile: both probes were in the centre of the heap.

Review of what went wrong with this heap…

What happened – did well in reaching temperature, so sufficient N to get there, but no staying power. Possible causes:

  • Exhausting N by turning a day late?
  • Poor mix with insufficient N in the first place due to a lower clover to grass ratio than assumed?
  • possibly there is something too woody in the evergreen leaves?
  • possibly would have benefited from additional insulation to be able to turn earlier to avoid exhausting nitrogen?

Composition Data processing for 160901

Heap ID 160901
container large black plastic
volume (init)
Material WLB loads density Nitrogen Green Woody Norm N Norm G Norm W checksum notes
Grass, clover, nettles, comfrey 1 0.8 0.5 0.5 0.4 0.4 0 1
shredded evergreen leaves 2 1 0 1 0 2 0 1
woodchip 3 1 1 0 0 3 1 one wheelie bin is three wheelbarrows
totals 0.4 2.4 3
Normalised proportions 7% 41% 52% 100%