On Mon, 27 Mar 2017 14:11:07 -0400, Gary Woods
wrote:

Judith in England wrote:

I sowed three different varieties in greenhouse a week ago today : container on
heated sand bed: thermostatic heater in greenhouse : and none have come
through. Previous years the first ones usually come through in three or four
days.

Is it possible that the greenhouse air temperature, and thus the upper part
of the seedbed, are cooler than usual? I often put a plastic cover over
the flats, as much to hold heat in as to keep moisture up; I use the rubber
heat mats, with a thermostat probe stuck in the flat, usually set for
around 80F, which it barely maintains in a chilly cellar under fluorescent
lights, and a plastic sheet tenting in the front of the 3-shelf array.

(This all on a home-made rig made of scrap plywood. A cabinet maker I am
NOT!)


I suspect that you are right: re the greenhouse air temperature in the night.
I can't think of any other logical explanation.
If there is no soon sign of life - I will cover them up at night and keep them
nice and warm!!



Cheers