Proper temperature for seed germination with a mat

I am using a heat mat inside a tent to germinate seeds. Seeds are inside a small container boxes inside some wet , folded paper.

Even though I have low power leds the temp tends to rise to 28-30celsius /86fahrenheit.

The boxes tend to get steamy. Is this too warm for the seeds?

Just wondering about a 50/50 failrate in germinating seeds. Are they “boilin”? What is a good temperature for a heating mat?

Does presoaking the seeds inside a water really help?
Does a product like rhizotonic help to germinate seeds? It reads about it in the bottle but how much is enough of that inside a litre spray bottle?

Any other tips how to improve germination/seedlings?

Thanks, great forum!


Welcome ! I will say this with the heat mat make sure and keep the paper towels or paper damp it will dry out quick. It should work fine for you. Good luck :v::+1:

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26-28c is a good temp.

Good call on the damp paper towel inside a Ziplock bag and then in a light proof container.
Ensure the light proof container cna transfer heat to the seeds though, I personally use a foil bag, mylar bags or one from the taco/burrito kit works well lol


My set up was a little different. Not sure about the folded paper method. I used root riot plugs in a tray with humidity dome. Heating mat under that hooked up to a timer for 15min on/ 15 min off in darkness. In 3.5 days they sprouted.
I’ve been 100% with germination.
I never checked the temp during germination


Ok so you give consecutive boosts / cooldowns with the mat?

You don’t want it to get to hot. Warmth is key. You could also put some between the heating mat and your seeds i suppose.

No don’t give bursts, use a controller it will minimize that effect and keep it much more constant.

Get a good tail on the seeds first then toss them in your rapid rooter or nursery pots or whatever you choose solo cups etc.

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