Cool temperatures for seedlings...

[SummerSky]

Up until this year, I've always started my tomatoes in my bedroom, since that had the most space, up until we moved. This is a new problem I never really thought about much before.

In the new house, the space where I designated my seedling station to be gets down to around 50 degrees at night (this is about 8" away from the T-8 shoplight where my onions and celery currently are, which I turn on at night to keep them a little warmer). Is this too cold for sprouted seedlings? It's a south facing solarium that warms up during the day (mid to high 70's on a cool, sunny day).

Right now, I have a couple trays of newly sprouted peppers, eggplants, and dwarf tomatoes in the warmer "nursery", but it can only hold two trays. I need to move these trays over into my seedling station to start my tomatoes, but I don't really want to murder my seedlings...

[jmsieglaff]

No problem. My seedlings live in the upper 50s/lower 60s basement, until I move them to the cold frame in late April until plant out in mid May. They routinely experience nights in the 40s with no problems--either at seedling stage or later in life.

[Ricky Shaw]

You're essentially cold treating, night time 50-55F, and that typically lasts around two weeks and is time focused on first leaf formation. The plants would certainly continue to grow in those conditions for as long as you'd like, the question is will the growth have advanced sufficiently for your plant out program.

http://www.kdcomm.net/~tomato/Tomato/start.html

[SummerSky]

Originally Posted by jmsieglaff

No problem. My seedlings live in the upper 50s/lower 60s basement, until I move them to the cold frame in late April until plant out in mid May. They routinely experience nights in the 40s with no problems--either at seedling stage or later in life.

Awesome, thanks!

[SummerSky]

Originally Posted by Ricky Shaw

You're essentially cold treating, night time 50-55F, and that typically lasts around two weeks and is time focused on first leaf formation. The plants would certainly continue to grow in those conditions for as long as you'd like, the question is will the growth have advanced sufficiently for your plant out program.

http://www.kdcomm.net/~tomato/Tomato/start.html

I think they should be ok. At least I hope so. When it warms up outside, the solarium warms up quickly. The eggplants might stall on me for a while, but they always do that for me.

[Ricky Shaw]

From all I've read the cold treatment is very beneficial, just takes longer. I've got seedlings in cold treatment, 55F dark 12hr and 63 F with the T-5's on, and some in the open room. After just a week the one's kept out and 70's F constant are noticeably further along.