Help! Are these maggots in my compost?

A soldier fly larvae


Sam emailed in a photo of some brown grubs he said have been populating his compost bin, concerned they might be doing it more harm than good.

But good news Sam, these little brown larvae are one of the good guys!

They are the larvae of Hermetia illucens,  or more commonly called black soldier fly. 



Black soldier fly larvae (BSFL) are actually beneficial to your compost heap or bin because:

  • they’ll help prevent houseflies from laying their eggs in your compost.
  • they actually help in the breakdown of your compost

So don’t panic if you see these little brown grubs in your compost bin – they are giving you a helping hand!

An adult black soldier fly

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