The possible life span of an earthworm and it's practical length are likely very different. One specimen of Lumbricus terrestris (the common north American nightcrawler) was reportedly kept alive in a laboratory for 15 years, and an Eisenia fetida specimen was reportedly kept alive in lab culture for 7 years. In nature, however, being subject to environmental extremes and continually threatened by a vast number of predators, earthworms likely live no more than a few seasons.

Different species survive during climatic extremes differently (now there's a shocking statement! ::grin::). Deep burrowing species will delve below the frostline and go into hybernation-like states to wait out cold or hot weather, emerging either after a physiologically proscribed time, or after being tapped by some environmental cue. Mature surface dwelling worms, on the other hand, typically die during extremes of climate, leaving behind cocoons that easily survive being frozen, submerged and even dehydrated to hatch healthy young when conditions become favorable once again.

Make sense?

Kelly S

Thanks Kelly,
Great forum, been reading posts for a couple of months.
Lots of good info, and a variety of ideas.
Since I have a room I don't use , I guess I'll put some holes in the 24qt. rubbermaid, fill it with shredded news, couple hundred earthworms, some 3-4 day old kitchen waste and try that this winter. Maybe a second bin with leaves from the concrete slab.

Im still a newbie, but I thought Esinia Fetida were the "best" for bin culture- because they are such voracious eaters, they can process the bin-foods without too much stress- Earthworms seem to do better in old compost/ leaf pile in my experience.

good luck!