Does a seedling require the same temperature as it did before germination?

Evening all,

I wish to prioritise the warmest highest levels in my polytunnel and I was wondering if it would be OK to drop a few levels the seedlings which have emerged and replace them with newly sown seeds?

I say this because I am wondering if the seedlings can handle slightly cooler conditions as I can recall reading a seed packet some time ago which stated different temps (highest required until germination) on it.

Does it relate to specific plants or is there a general consensus for a higher temp required for germination?

Thanks for your help (if you can understand what I am getting at!),

Samuel

 

I see no reason why you shouldn't drop the seedlings down a level or two. I have seedlings that were started in an electric propagator, having moved them out onto a window sill for a week in a warm room I have just moved them again into an enclosed unheated porch. If you move them on gradually they will cope with the lower temperatures, acclimatising slowly, but obviously it's not warm enough to move them into a cold greenhouse yet.

Most of my seeds are grown at the same heat level and seedlings are all treated the same way regarding moving them to lower temperatures. There are some seeds that have specific germination requirements but that is usually stated on the packaging. I have a number of trays of perennial seeds currently in a heat situation that will have to be plunged into a false winter, ie my fridge for three weeks.

 

Onions benefit from some warmth during germination, but then don't need any after germination.

Brassicas don't want heat during germination, nor afterwards.

Tomatoes do best with a bit more heat during germination

so ... lots of variations I reckon. Best to look up the details for the specific crop(s) you are growing.

 

The other thing about dropping them to a lower level on the staging is the matter of light. What might seem like a small difference can result in leggy seedlings.