I have killed off sets of seeds letting them get too hot in the pots, and have also had slow germination where by everything seemed to start sprouting after the medium went completely dry and then was rewatered (Which often corresponded to reseeded plants popping up too). You can try germinating on some wet paper towel to see if they are good and your potting mix is at fault in some way.

Crossing would not affect germination.

How many seeds did you start for each variety?
How do you save your seeds (prepare them??
How old were the seeds?

I'm assuming you fermented your saved seeds, possibly as did Spiced ham above, and the questions asked above were fine.

Just one more question.

If you did ferment them what color were the seeds when you finished and they were dry?

It sounds as though you've been saving seeds before but I thought it might be worthwhile to also ask about color b'c more than once I've overfermented seeds and they were almost black with no fuzz, which is not good news. If they are just a dark brown those usually are OK, but what you really want are light buff colored seeds with nice fuzz.

Finally, did you change anything at all this year with regard to the soilless mix you used for germinating seeds or anything else you might have done that you didn't do before?

I almost forgot. How long have your current seeds been sown with no germination?

Carolyn

Wow - you all are quick! The seeds were not old, just from last season's crop. They were a nice buff color with some fuzz. I have seen the darker (fermented) seeds and I do not plant those. I did not try them on a paper towel, but I will try that with a couple of the seeds left. We have used those expandable peat pots to start them for the last four years. We then set the peats pots into those clear egg containers, kind of a mini greenhouse, they fit perfectly, and placed them in our garden window. The moisture level is fine, humidity good. I have baked things in the past... The seeds have been sown for just shy of a month. :(

I can't think of anything different that was done. I will just have to buy plants, right? I so appreciate your follow-up & additional questions to make me think about what may have happened! Thank you so much, Carolyn and Spiced Ham!

I knew I was going to forget a couple of the questions...

We separate and dry our seeds on a stainless, fine wire rack. We store them in paper bags inside our house (they don't get too hot or too cold) We started about two or three seeds in each cell - we do not have a large garden, so there were two dozen cells (1 dozen plum, 1 dozen brandywine)

The only time I have had a mass lack of germination was when I let the peat pellets dry out-- but it sounds like yours are covered and staying wet.

Were the paper seed packets exposed to any moisture?

How long did you soak or ferment the seeds?

How ripe were the tomatoes when you saved seeds?

In zone 5, if you wanted, I think you could still start some more seeds, if you're quick and can put the lights close. I am zone 7, and I started some a week or two ago!

Jess