Reasons compost heap smells terrible

Article content

A. That particular odour emanating from compost is often caused by an overload of high-nitrogen materials like young, soft, green weeds or plant parts, freshly mowed grass and manure. These need to be balanced with dry, brown material like dried leaves and shredded newspaper.

Article content

Excess nitrogen in a compost heap is released as ammonia, characterized by an “eau de horse barn” odour.

Nitrogen in the form of ammonia is wafted into the air also in alkaline conditions, which sometimes occur when an excess of alkaline elements like lime or wood ashes are added to a heap.

Another possible cause of a smelly heap is excess moisture, because wet conditions drive out oxygen, which aids decomposition. Decomposition without adequate oxygen is a malodorous process.

Article content

For the speediest possible decomposition and a heap that has a pleasantly “earthy” smell, chop or shred materials going into the heap, keep soft green (high-nitrogen) materials equal in amount to dry (high-carbon) materials, maintain an evenly modest level of moisture in the heap, and fluff it up occasionally to introduce fresh air.

Q. I planted one variety of fava bean this year, and refrained from harvesting from a few of the best plants, whose seeds I want to save for planting next year. At what point should I gather the pods for this purpose?