Mold on seed starting trays? Tips on germinating eggplants?

[Svea]

Hello, I started some tomatoes and eggplants about 2 weeks ago and within days there was a thin layer of white mold on the substrate. It's 75/25 organic seed starting mix to organic worm castings. I set it out in the sun for the day and it burned it off but it's come back. The tomato seedlings are thriving and don't seem to care about it. My eggplants haven't sprouted yet. I have them under a grow light and I had accidentally overwatered them until a few days ago. I used the same soil and grow lights last year.
1. Is this something I should worry about or is it no big deal? What could be causing this?
2. Any tips on getting eggplants to sprout? I'm starting to get a little worried my seeds aren't good anymore...

Thanks!

 

[DirtMechanic]

The thing about seeds is everything they need is onboard. That is one reason why seed starting mix is just a medium. Are you using heat mats? Is it cold in that room? I doubt it is 80f. Some plants are heatseekers and some are not. Search for seeding temps on the site. I want to say @Chuck posted a plant temp list once upon a time.

 

[Chuck]

https://sacmg.ucanr.edu/files/164220.pdf

I would replant with fresh seeds. The white mold is "probably" harmless and is caused by the soil staying too wet.

 

[Svea]

The thing about seeds is everything they need is onboard. That is one reason why seed starting mix is just a medium. Are you using heat mats? Is it cold in that room? I doubt it is 80f. Some plants are heatseekers and some are not. Search for seeding temps on the site. I want to say @Chuck posted a plant temp list once upon a time.

It's 72F in the room. I haven't used a heat mat before but I think I have one somewhere.

 

[Svea]

https://sacmg.ucanr.edu/files/164220.pdf

I would replant with fresh seeds. The white mold is "probably" harmless and is caused by the soil staying too wet.

Will do. Is putting them in a moist paper towel until they germinate and then potting them inadvisable for any reason? I want to make sure my seeds are still good at the same time because they're a year or two old.

 

[Chuck]

Will do. Is putting them in a moist paper towel until they germinate and then potting them inadvisable for any reason? I want to make sure my seeds are still good at the same time because they're a year or two old.

It will be perfectly fine if you have proper lighting.

 

[DirtMechanic]

It's 72F in the room. I haven't used a heat mat before but I think I have one somewhere.

I use a bit of cardboard to mellow my mats to 80f. One could buy a controller too I guess.