On 28/03/17 10:28, Judith in England wrote:
On Mon, 27 Mar 2017 22:24:29 +0100, Jeff Layman
wrote:

On 27/03/17 16:07, Judith in England wrote:


I sowed a dozen or two 3-year old Golden Sunrise seeds in an 8cm pot and
put it in a heated propagator. Germination was pretty good in less than
a week, and the seedlings are now a week on and look fine.

Thanks: I did wonder about that as some of my seeds were from last year
(perhaps year before) and I wondered if they were too "old" !
But your experience says not. I think as someone has suggested it could be the
night time air temperature.

Doubt it. My propagator is in the greenhouse. When the sun is out I turn
off the propagator as it get to 35C+ inside. Sometimes I forget to turn
it on again and on a cold night the temperature can drop to 8, or even
below in the greenhouse, and only a couple of degrees above that in the
propagator.

IIRC, some seeds germinate better when given cyclic temperatures - hot
in the day, and cool at night. But I doubt that the tomato is one of
them, being essentially tropical in origin.

--

Jeff