"B & J" expounded:

At one time my parents used fresh horse manure as a heat source in a hot bed
to start seedlings in the spring. A foot and a half deep rectangular hole
was dug in the ground in the fall, and it was covered with a south facing
wooden structure with an old window on hinges used as a cover. In the spring
(middle of March-zone 3) a foot of manure was placed in the bottom of the
hole followed by a six inch layer of straw. The seeds were planted in trays
and placed on top of the straw. Enough heat was generated by the decomposing
manure to keep the structure frost free. On extremely cold nights a horse
blanket was put on top of the structure. It was the poor man's way of making
a green house.

I saw manure-heated greenhouses over in England, and these weren't
poor-man's outfits! It was neat, I'll bet Mike Gilmore (I think
that's his name), the guy who is renovating that beautiful garden over
in England who posts here occasionally has the same thing with his
greenhouses.


P.S. Well rotted cow manure works great, but I prefer sheep or rabbit
manure.

Absolutely. I've got lots of rabbit poop available right next door,
my neighbor raises rabbits and is very involved in 4H.

--
Ann, Gardening in zone 6a
Just south of Boston, MA
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