Inconsistent seed starts

[Anthony_Toronto]

Planted 114 seeds on the 25th, have had great luck in the last 4 years with soil-free seed started mix, but this year's mix seemed to contain more large chunks and way more vermiculite. First sprouts were out on the 28th, but only have about 35 up or poking through the soil right now, compared to more than 100 of 120 up two years ago on day 5 (and even more last year, though I did not note the number). Lots of fresh seeds and some older ones. Given the number that are up I want to get them in the sun, but I find that getting the seed tray in the sun (with the lid off) always makes germination rates for the remaining seeds fall off considerably. Cant leave the lid on the tray to keep the ungerminated seeds moist or everything will roast in the sun. How much longer can I risk keeping the few that have germinated out of the sun, to allow the ungerminated seeds to have a better chance to pop up?

[matilda'skid]

Get out your razor blade and cut up the plastic if there is a pattern to this sprouting. Hopefully the ones that sprouted are not scattered all over.

[ireilly]

Put it in semi-shade, filtered sun, or filter the sun yourself with some shade cloth or something translucent. As long as you get some of the right light and some infrared (heat) it will help. You're right, you don't want to steam the seeds.

[Gobig_or_Gohome_toms]

I agree with the razor blade comment cut squares the size of the cell to help in keeping them moist.

[Anthony_Toronto]

Ended up cutting up some patchwork plastic wrap to cover the ungerminated cells, but given the low overall germination rate I was cutting pretty big pieces. I thought I planted plenty of extras, and some varieties did well, but as of the end of day 8, have only 1 of 9 KBX (poor germination rates last year also), 0 of 6 Paul Robeson, 1 of 6 black krim, 2 of 9 Cherokee Purple, 0 of 6 Green Giant, 1 of 6 NAR, 1 of 6 stupice, 0 of 6 bloody butcher, and 1 of 6 black cherry, and several of these were brand new seeds. After 2 days in the sun I think 2 or 3 of the 60 ungerminated seeds have popped up. Might have to set up some more starts...

[barkeater]

Anthony,

What is the air temperature at night? When I started my seeds in the furnace room where it was a constant 78-80 degrees, they were all up in 3-6 days. This year I started them where the air temperature was from 63-70 degrees and it took 7-10 days, and some are still not up at 11 days.

[Anthony_Toronto]

It was in the range of 75 or thereabouts, and I did it in the same location I used for the last 3 years (with just about everything up in 3-6 days as you experienced), but changed the starter mix this year because the one I used for the last few years was not available, and I think it might have made a difference (and maybe some bad seeds).