Sounds like the light was the biggest change you made, so it's reasonable to start there. It's hard to tell from the picture but the plants look a bit leggy.

Low light isn't going to cause tomato leaves to dry up.

Was the mix moistened well? We've discussed how hard it is to wet mix if just applying water from the top. If the roots hit dry soil, you'd expect this to happen. That is, dry mix will shed water. You water it, and the water will just run down the sides and out the bottom. You can have a layer of wet soil on top of a layer of bone dry soil. I've heard that complaint about Promix. You might just pull out the plug of an affected plant and see if it's dry.

I guess if not that I'd worry about some bizarre fungal issue. But you were careful about cleanliness, and Promix is sterile. I have a hard time seeing how bugs could get in.

Now, Promix has, I understand, just minimal fertilizer (fertilizer isn't appropriate for small seedlings), and I think you're supposed to fertilize after a few weeks. I'd think it odd if lack of added fertilizer caused these problems, though.

I'd blame the ProMix too. It contains NO fertilizer, so you need to add some when the second leaves show but, as the above poster said, that wouldn't account for them dying. Your mix looks very dry and it seems to me that the lights and the domes ARE baking them. That would account for dead leaves but healthy stems....

Linda

A lot of good questions
here.
I will see if I can put them into perspective.

I used these lamps last year on other seeds at
about the same distance. They worked back then. I will seek to put them closer.

Yes, I would call them leggy but I recall tomatoes in the past as looking
similar. How much leg should they have when only the primary leafs are showing?

The domes are simple clear plastic shallow open
bottom "boxes" that fit over the seeds to help keep seeds moist until
they sprout. The domes are not used
after that. The temperature was
monitored when in use and it was kept to about 65-75d just on room ambient
temperature. If they had been cooked then the seedlings would have dies or
would not have spouted. I have a very
high germination rate in every case, sometimes too much so. (:

When I set up the initial seed nursery I saturated
with water then drained the soil. The
pots remained in water long enough that I am sure that there would be no dry
spots in the soil. After they drained, I
placed the seeds, added a covering of soil, and misted the tops to moisten them.

Continued:

Part 2:

I wondered if the Promix is unacceptable but
again, I have been using it in the past for seeds. I even at times of poverty used recycled soil
but that was not the case this time.

The top looks dry but immediately below the
surface it is moist. I had been watering
from under and spraying the top. The
first batch was extremely dramatic in the die off and I suspected that
something might have contaminated the sprayer but I used a new one for cycles 2
and 3 and, at the moment, they seem to be in stasis. If they still die off than
it was probably not the sprayer. I have
been using tap water and we have extremely good water quality but still things
do change. I wonder if I might run a
cycle with distilled water with the next. Run.
However, I have been using tap water for years now.

There is plenty of air circulation and the lamps
are not heating the soil. CFLs are not
warming the surface. I measured it to 70d-75d.

Someday I will assemble a Raspberry-Pi computer with
a sensor to take periodic readings and watch what is happening but, as
mentioned, my set up does seem to be quite stable.

So, for now, it looks as if I will bring the lights lower and watch the soil temperature more closely. If the colony collapses again, I will inspect the roots.

It was suggested that I use a fertilizer.
Any suggestions?
Thanks of r all the comments.
Maybe I will get to the bottom of all this
before too long.

Iv'e had the same issue with the Promix not giving enough water, being super wet on top but moisture not getting to the roots. I lost a few seedlings to this earlier this year. What has been working for me is using one of the plastic spray bottles from home depot and getting a nice strong jet going, then using the jet to sort of pierce the Promix with water. I revived a few 1wk seedlings by sort of lasering the water around it. Did notice on a few other tomatoes that died, there was just not a lot of moisture getting to the seed. So going around it helped a lot. Good luck

Sounds like you should try a different medium. I know ProMix is highly rated but it may be your issue.

I would never fertilize a seedling that small. If my mix required that I would look for a different one.

I am beginning to wonder if there is something wrong with this one bale of Promix....

It can't hurt to try something else.

That would actually be very interesting to do some pots with Promix and some with something else, and see a direct comparison. That is, if the only variable is Promix, it tells you something about Promix.

Next batch will be from another bag of Promix, and one more from a different brand of soil.

I sent in a message on the Promix web site and wonder if they will respond.

Not much much of the problem could e discussed because, for some reason, they limit the response to 500 characters. Maybe they have trouble concentrating and cannot read that much information all at once.

sorry but promix is overrated and overpriced, at least around here.. it's a bland, basic mixture of basically peat and perlite, and maybe some fungi depending on which "model" of promix it is.

the promix with fungi is useless to seedling during their first 2-3 week. perhaps after transplanting it will have some benefit, but by then you might as well just use a fertilizer with the fungi. as soon as two true leaves appear they need fertilizer which promix lacks. you might as well just buy a seed starting mix that already includes a very mild fertilizer dose. a $4 bag of Mircle gro seed starter mix contains what is found in promix and has some food to get the seedlings going.

I use Espoma as my go-to mix, I love it. It has organic fertilizer and a good amount of perlite.

Pro-mix seems overpriced to me. I was considering buying some this year, but it was very expensive and I don't like mixes without any nutrients in them.

> I use Espoma as my go-to mix, I love it. It has organic fertilizer and a good amount of perlite.

Espoma is great. one of the best organic fertilizers out there IMO. i love how their fertilizers are "green" in that they are made using solar power. http://www.espoma.com/company/solar/

they just recently released liquid form fertilizer: http://www.espoma.com/liquids/
they all have kelp. not economical for large garden plots, but excellent for containers and small beds.

They make a great organic mix, why not give it a try?

I feel everyone is blaming what they can't see but what I see is a poor setup for starting seedlings. There are 3 things I see that are obvious if you want to repeat with a few alterations.

The light setup is the biggest problem. Wrong light, wrong spacing. The large pots make it harder to achieve proper water and light to each seedling. Ditch the large pots for shallow trays to get seedlings started. You can always transplant seedlings into those pots in 4-5 weeks.

ProMix may not be the best seed starting media but it beats everything mentioned. I use the ProMix BX with micorhizzae and biofungicide for everything, start to finish, and no hint of those problems.

interesting, 4" pots are too large?

Let me say that I have been using various arrangements of this same setup for years. Maybe I have simply reached the worst possible combination.

I am beginning to believe that it actually could be a contamination in either the water or the ProMix. I placed a message on their web site but have not yet received a response. It has only been three days so I do not expect an answer so soon.

It may be an extreme but I will do this just for the study if nothing else: New bale of Promix and distilled water.

Last year, I used 4" pots, transplanted to 1 qt pots, and used the same ProMix BX with micorhizzae and biofungicid. for soil (new bale this year though).

This picture was taken on 4/18 last year. I seriously doubt that I am going to see anything like that this year. I started them in early February as I did this year. I never used any fertilizer for any set.

Here is the picture from 4/3/15 using 2 40W florescent lamps that are further away than what I have now. Maybe the CFLs are the problem but I have used them before to germinate seeds.

The 4th set (Rutgers this time) has not germinated as of today, it has scarcely been a week. Same pot size, same (unused) promix soil. I will try different lighting and lower them as I monitor the temperature.

I am going to use fertilizer on one of the two sets that seem stressed.

The plot thickens....

The lighting setup isn't causing the problems we're trying to help with. Leaves are all drying up because of poor lighting? Nope. That's not how it works. Let's not get distracted by lights. I agree that this setup doesn't look optimal lighting-wise, but that's not the problem.

The leaves in the first batch curled up and died but the two trays in the second batch simply stopped growing. They are not sprouting the secondary leaves. Either there is still some hope here or maybe they are getting ready to bail out too... Time will tell....

Poor lighting! Those lights will burn leaves from the heat they generate and the heat can't escape well with the hard shades. With large pots water may be everywhere but at seedling roots and you won't know it.

A real mystery. I guess what I didn't absorb from the previous discussion is that you've been doing it this way for many years, and something is wildly different this year. I see why you're bringing this to the attention of ProMix and have suspicions of contamination.

No, fluorescents won't burn leaves even if they're almost touching them. And the OP was monitoring the temperatures under the covers, I believe.

Agree with Barrie for the most part. It seems unlikely to me that it is the Pro-Mix causing your issues. We can think we are doing the same things every year when starting seeds but that isn't always the case. It's easy to overwater and/or underwater without realizing we are doing it. The humidity, ambient temperature, and amount of air circulation in the seed starting area l be slightly different year to year which will affect the seedlings and potting mix differently. Not to mention that switching to a completely different light set up has its own learning curve.

That said, I think your main issue is water. You are either giving them too much or too little. It's the most common cause of stunting and failure I know of for seedlings. You are either giving them too much and causing root rot or you aren't giving them enough and they are parched. If you use a pot too big for the seedling it is very easy to do both, sometimes at the very same time.

Oh, and I do believe your lights are less than ideal and the legginess of the seedlings is an issue. A leggy seedling is not a strong seedling and it won't take much for them to fail (such as what I mentioned in the above paragraph). The bulbs you have definitely aren't providing enough light at the height you have them and/or for the duration you have them on.

Rodney

The discussion here promotes a lot of rethinking of my set up.

Right now, Promix is an unlikely suspect and I will use soil from a new bale for the next batch anyway. The more I look at the situation I am trending towards too much water being the problem although I am not seeing any yellowing but the plants may be too young to show that.

I suspect that that first batch damage might have been caused by a contamination in the spray water bottle and maybe that got me onto a watering (over watering) trend.

The next two trays do not show the die-off of the leaves but they did seem to stop growing. I think this is another indicator for two much water. Maybe I killed off the roots. I will inspect one or two of the plants later today.

I checked the temperature from the lamps and I am not convinced that that is the problem. Lowering the height of the lamps might help to prevent them from getting leggy.

You could examine your seedlings for signs of something but the obvious is that the norm is missing.

Plants should be more stout, more upright and darker green.

I would suggest removing shrouds of lamps to allow better light but I don't want to be the cause of a house fire.

On the next batch I would suggest you pre-moisten the Promix prior to sowing the seeds so that it is damp but not saturated. Use smaller containers such as 806 cell packs for the first 3 weeks before potting up to 4" containers. Bottom water the cells but do not leave them sitting in water. I use a separate tray for watering and transfer the cells or pots into that tray filled with 1/2" - 1" of diluted fertilized water and when they have soaked up the desired amount I move the cells/pots back to their own tray. I would also go back to your fluorescent lighting.

Like barrie, I use ProMix BX with micorhizzae and biofungicide from start to transplant. I've gone thru at least a dozen bales since I started using it and have never had a problem with it.

It does seem unlikely it is the Promix, but if I had problems with seedlings dying I would certainly try switching it up.

The lack of light can contribute to seedlings drying up and dying. If they are very leggy, they are very vulnerable to any kind of issue. Regardless if it is a direct cause, those seedlings do not look like they are getting enough light and that should change. IDK anything about those lights, but if they are very hot you might want to consider an alternative, and IMHO definitely get rid of the domes, they do absolutely no good.

I would definitely start them in seed starting trays. It makes it much more difficult to overwater, but it also makes it easier for them to dry out and die. With the dry heat in my house, I typically have to water seed starting trays every day.

Just my thoughts...

Update on the Update....

Procrastination is afoot here..

I kept on putting off doing anything with these seedlings and they actually recovered! Most are sprouting their secondary leaves and standing tall.

I suspect the first batch was, in fact, injured by a contaminate in the sprayer bottle and killed off the primary leaves. All of the stems remained green and strong but I guess because there were no leaves they died off too. The next three trays fared much better without any spray.

Soon, I will be transplanting them "neck deep" into quart pots half filled with promix.

My "Fourth of July" tomatoes may just produce by,... well,.. the fourth of July.

Just out of curiosity, what do you think was left in your sprayer bottle?

It could have been diluted bleach. I did rinse it out but maybe the interior was permeated and I wonder if it leached back out. It is only a guess. It can no longer be tested as I now use it 50% bleach/water for other purposes and it is clearly labeled.

The plot thickens.....

Recap:

Tray 1 (Eros:Mail Order) sprouted as scheduled, grew to 1 1/2" when the primary leaves died off and then the stems died back.

Tray 2 and Tray 3: Eros and 4th of July respectively and from different vendors. Started 3 weeks after tray 1. Exact same pattern and also lead to failure.

Tray 4: Rutgers, 3 weeks later: Left over from my stock from last year which were purchased 40% off from a discount store. They are performing incredibly well. Secondary leaves are 2 - 3 times larger than the primary leaves and the stems are hairy and ready for replanting.

All four trays used the same potting soil, same 18 pot trays, same lighting, same temperatures, same watering (tap water). All trays and pots were cleaned in the same way using soap and rinsed with dilute bleach and rinsed again.

I still have some Eros seed and plenty of 4th of July seed so I will try again on those. I doubt that starting too early in the year was a problem but this might show something to that effect.

Each set was started about three weeks apart.

Bizarrer and bizarrer......

Where did the seeds come from? If your seeds from last year did great and the new seed is doing terrible, and all the conditions are truly exactly the same, then the culprit is the seed.

I would have figured that except for the fact that the 4th of July seed were directly from Burpee on-line. Both purchases of Eros were from Plant World (UK) on-line 4 weeks apart and the Rutgers were from Ocean State Job Lots (also Burpee) purchased at the store last year.

I also thought that there might be some commonality on sources but that doesn't seem to be a link.

Right now, the only difference seems to be the fact that the seeds that failed were purchased on-line. If they met with irregular temperatures or something in shipment then I doubt they would have sprouted in the first place.

As I said, I will set up another batch of seedlings and it will be very interesting to see what happens. If they grow then some factor affected the first two plantings. If they also fail, maybe I will take up knitting instead. (:

Update on the Update Update....

I am beginning to see that it may be "Damping Off", Now that I have seen pictures, yes, it looks exactly like it does in the pictures.

One reason for it suddenly happening is that I may have chosen two seeds that are, in fact, prone to disease. Coincidence? Maybe...

The Rutger's tomato is both a strong plant and is not susceptible as noted from Burpee.

The presence of moss on most of them, including on the soil of the Rutgers, may have changed the pressure of the Hydrogen but even Burpee representative says that it doesn't look that bad but maybe it doesn't take much.

Meanwhile, I have an ICU triage section where I have a few premies under special care. However, damping off, even if they survive will probably be weak and stinted plants. Still, I want to see it through if nor nothing else than the study of it.

After all my inquiry these last few weeks, I am surprised is that no one mentioned Damping Off here, on another forum, from two agriculture centers and a garden center.

Now, I am going to bet that a lot of people will mention that they have seen it and, as many guys claim, I can honestly say "It has never happened to me before...." (:

Well now that you mention it, I had Damping Off this year - and I've never had it before! I suspect mine is due to mouse feces in my bag of potting mix because I discovered a fiberglass nest in there! I when I first saw it, but figured that the mouse droppings would add nutrients. I was wrong. My seedlings (which I had started on damp paper towel) grew a little, and some even got their second leaves before suddenly falling over dead :(

I am re-sowing many of my seeds that I lost and sterilizing the potting mix in pots in the microwave, then watering with a splash of peroxide in the water.

Linda

I have a feeling that your efforts will make your kitchen smell like a sewer and won't accomplish anything. Since you were able to purchase ProMix just ask for the ProMix BX with micorhizzae and biofungicide and Damping Off will likely not occur again. It has been a staple media for me for many years now and my Damping Off days are gone.

But I still blame your lights for other issues as shown by images.

There is no evidence of sour soil, if that is what you are suggesting, and I do use the Pomix with micorhizzae. I have started the seeds for another round of the Eros and the "4th of July" tomatoes.

There is also a set using four 48" florescent lights.

Time will tell...

"After all my inquiry these last few weeks, I am surprised is that no one
mentioned Damping Off here, on another forum, from two agriculture
centers and a garden center."

Damping off wasn't mentioned because there was no evidence of it in your prior posts. Damping off happens quickly and causes the stem of the seedlings to narrow at soil level and the seedlings fall over and wither. It doesn't stall the plants for weeks, it doesn't make them leggy, nor does it cause the cotyledons to curl up and die. If your seedlings are now having problems with damping off then that is something new that has popped up in the week since you posted your last update.

"The presence of moss on most of them, including on the soil of the Rutgers"

Damping off and moss on the soil (most likely algae) are both signs that you were overwatering.

Rodney

Ok, maybe I am now back to square one... ):

I am learning more about Damping off and maybe this is not the case. The stems remained sturdy and the seedling have roots.

Thanks for the information on damping-off.

In the Promix that Barrie mentioned, it is the same formula that I use, it is the biofungicide that protects from damping off. They have several different mixes but only one has both micorhizzae and biofungicide.

Just FYI, Microwaving my soil-less mix didn't stink at all! ( I was surprised!)

Thanks for the recommendation of the Pro-mix with micorhizzae and biofungicide. I will get some of that :)

Edited to add that the one with the biofungicide is only available in the USA :(

Now back to the original discussion.....

Linda

I would like to point out that you must be careful in microwaving/heating the soil because if you get the temp over 200 degrees, there is a chance a chemical reaction will occur releasing tannins into the soil, which will actually poison your plants. So basically overheating the soil will render the soil useless. This is often accompanied by a bad smell as well.