Average germination temp

[beeterforit]

Hi All
Is there a" goldilocks " temp for general seed germination using a thermo controlled propagator
tomato and aubergine like 30c lettuce do not like above 24c what temps for a good average ?

[veggiechicken]

There's an interesting chart at Temperature effect on vegetable seeds - percentage germination that links soil temperature, days to germination and % of seeds to germinate.
Its in Old temperatures (F) so you'll have to convert them if you're a young un

[BertieFox]

You don't "need" 30C for things like tomatoes, peppers and aubergines, it's just that they germinate more quickly at those temperatures. As long as they are not too wet so rot can occur, seeds of these things can be germinated at anything from 25C. I suspect more seeds are destroyed in in seed propagators through them getting too hot when the sun comes out than those that fail to germinate from temperatures being too low.

There are some vegetable seeds which are thrown into dormancy (e.g. spinach) if the temperature is too high and most 'ordinary' vegetables like a cool 60F or so.

There are of course some tropical and sub tropical seeds that really will never grow unless they reach the higher end of the spectrum.

Thanks to VeggieChicken for posting the link to the temperature chart. It's interesting to see just how high temperatures need to be for optimal and rapid germination. But I have a theory that things which are kicked into life in such optimal conditions won't be as tough and hardy as those allowed to take their time, as in nature.

[veggiechicken]

My concerns are that seedlings germinated fast and at high temperatures would be "shocked" when they are taken out of the heat and into normal temperatures..
I'd prefer to let seeds take longer to germinate at cooler temps. Seems more natural to me

[TrysHard]

About 25c is my experience, but my propagator cannot be regulated so I open the vent.

[FlawlessVictory]

My fish tank is set to 25c and my seedling sit above the light.... I've had my chillies,aubergines etc come up with way.

[Zelenina]

That's a very useful chart VC. I've come across it before and I think it was probably in Celsius originally, and converted to Fahrenheit for Americans. Because it's very easy to convert.

From left to right the temps C are 0, 5, 10, 15, 20, 25, 30, 35, 40

I'm not so young but °F are only a dim memory for me now, though I still sometimes measure things in feet and inches.

[Gema13]

Personally I find the best average soil temperature is 22 degrees. Higher and you risk literally burning the roots.

[Kristen]

My concerns are that seedlings germinated fast and at high temperatures would be "shocked" when they are taken out of the heat and into normal temperatures..
I'd prefer to let seeds take longer to germinate at cooler temps. Seems more natural to me

I've been germinating at "relatively high temperatures" (around the optimal mentioned in the links / discussion above) for years. Can't say I've noticed any subsequent problem with the plants; they will have moved off propagator as soon as germinated (although I don't immediately take the lid off as recommended, I open the vents progressively, and then remove the lid).

Only observation I have is that regular seeds (all vegetables, and ornamentals that are not "difficult" to germinate) come up all-at-once when germinated at the temperatures I am using, which I find convenient when pricking out. But I've not sown any side-by-side with a seed tray at a lower temperature to know if they might have been more erratic.