‘Good Compost For Horticulture’

Jim Cronin

  • Proper ratio of ingredients – 50% brown : 50% green.
  • The stack or windrow is ideally 1.5 metres high x 1 metre wide and as long as required.  The longer the better.
  • 10% of the stack is soil as an inoculator.
  • The gardener starts with a brown layer well fluffed up of 30 cm depth.
  • After this the material can be layered or pre mixed on a slab.  The important consideration is that the brown / green ratio is observed.
  • It is crucial that the following happens with temperature:
    • Slow climb in temperature taking 5-7 days.
    • The temperature rises to 63 degrees Celsius and stabilises, that it remains constant for six or seven days.
    • A gradual decline happens after six days and the temperature settles to the ambient temperature for the time of the year.
    • Temperature of the heap is stable and no further sudden rises in temp occurs.


  • Excess moisture (rain).
  • Smearing the ingredients with a tractor loader bucket or similar.
  • Compaction and anaerobic spots.

Good compost is one of the keys to a weed-free garden.  Our potatoes are weed-free at Garraunboy , Killaloe, Co Clare. They received no hand weeding and made a nice crop .

SEE PHOTOS: Poor & good quality compost produces these results.  1st photo is uncomposted.  2nd is composted.



  • Compost heaps are ideally placed in a sunny position.
  • If you can place the heap on soil or sod as opposed to concrete or tarmacadam.
  • The ration of ingredients is very important, so 50% brown, 50%green.
  • Brown material is an ingredient that is slow to rot and goes earth like / forest floor like if left in a bag eg straw, cardboard, soil, dry rushes etc
  • Green ingredients are quick to rot and go smelly and gunky if you leave them in a plastic bag eg household compost material such as tea bags,  coffee grains ,citrus , vegetable peelings.
  • So you start with a brown layer, say a generous amount of straw 25 cm.  Well fluffed up with lots of air.
  • Next a green layer of say 10 cm – thin is best. NB Spread the ingredients over the entire surface area.
  • Follow with a brown layer of equal thickness 10 cm.  Remember well spread out with plenty of air.
  • On you go …filling away ….the quicker that you fill the better .
  • Finish with a brown layer and a hat shape.  Cover with a tarp or a metal roof.

For more info and details on temperature, turning etc my composting course is available online from NOTS website.

Listen to a short podcast with Jim Cronin about composting here:

About Jim Cronin

More information and a short film on Jim’s farm here.  Ambassador since 2020 

‘How to build a compost cage’

Thomas O’Connor

See HERE the document Thomas put together for us with photos on how to build a compost cage for attracting worms.

About Thomas O’Connor

More information and a short film on Thomas and Claire’s farm here.  Ambassador since 2019 


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