Looks like there's still white mold on the surface of the soil, which indicates you've still got problems with damping off disease. Are you sure that window is as sunny as you think it is? Have you had an excess of cloudy days?

Can you move them outside? It's about time to start hardening them off anyway... getting them outside in the bright light and breezes might be just what they need. Don't be afraid to let the soil dry out before waterings too.

-Diggity

Here is a link that might be useful: Garden Imperative blog

Unfortunately the weather is changing in PA for the worse, 50's in the daytime and low 30's at night for the next week or so. So outside is not possible. There have a been more cloudy than sun days this year, but nothing abnormal from years ago. The only thing that is slightly different the last 2 years is that I replaced my windows with double pane thermal windows. I'm not sure how much this affects plant growth. I have always have that slight gray mold on the top of my soil every year in the past and that never really affected growth. I do wait until the soil drys out before watering and as stated previously I bottom water.

They look sick don't they?

Bob P.

Bob,

That's terrible. Has anything at all changed this year? Anything you can think of. What starter mix are you using? The second time you planted the seeds, did you plant in the same type of starter mix, from the same company? You're obviously not a novice, so I think you're going to have to do a bit of detective work on this one, because something is obviously different from years past. Are there any fumes coming from anywhere that were not there last year? Have you done any remodeling?

Too funny, I used to sell windows for home depot. The thing about enw energy efficient windows is they are treated with titanium dioxide. Same as in sunblock and house paint; prevents fading, heat transfer and UV light. Plants like the UV and most likely your new energy efficient windows are the problem! Put them outside in a cold frame, hopefully you saved your old windows for this.

Wow, so it could be the windows, how interesting. Bob did say that's the one thing that he's changed in the past year.

Hi Bob. I don't have a lot of advice for you, but I am in NEPA too and I have some extra tomato seedlings if you are interested. I would be happy to share them with you, if you aren't too far from me. I had better than expected germination this year and I couldn't bring myself to kill any, so I transplanted them all into bigger pots. I used a lot of growing lights. I am just starting to harden the tomatoes off today (will take in over the weekend given the forecast though).

To answer some of the questions above.

Last year I installed some of the windows and now I'm remembering the seedlings didn't grow exactly that well last year against those new windows but ok, but I also remember that the weather was nicer and the windows were open more so that UV blocking wasn't as much as this year with the additional windows. Last year the tomatoes were in the old windows without UV blocking and grew fine. I think that the new thermal pane windows are the issue.

Anyone here grow tomatoes/veggies/flowers in thermal/solar windows and are successful?

I do have a cold frame that I can put together today and get them out there. I just thought that it was much warmer and sunny in the house compared to the cold frame and that they would grow better indoors than out, but I can see that I'm wrong now.

Talonstorm, thanks for the offer on the tomato seedlings, but I only grow the Long Keeper variety in the house as you can't find them locally as plants, they store well into April for me so I plant them a lot. I normally buy all my other tomatoes so no problem purchasing.

Yes, the second planting was a different bag and "type" of seed starter soil but both manufactured by Ferry-Morse. It's hard to believe that both bags would act the same.

First batch I used bottled water, second batch I also added a little Captan.

I'm going to run another test with tomato seeds in the house, in the cold frame, and outdoors. Just to prove the soil, water, and UV issues.

Am I also wrong in starting to dislike these water retention soil mixes as they seem to never dryout quickly and may cause fungus problem that I didn't see before.

This year's seedlings were not planted in water retention mix, just old fashion seed starter mix.

Thanks for all the replies!

Bob P.

Bob -

I'm having similar issues but not as severe as yours - but I did plant them in one of those water retention mixes - I'll never do that again! They just don't seem to dry out, and therefore are giving the typical over watered symptoms (Yellow leaves, a little crisping at the end, and eventually the leaves fall off).

It's terrible, but WAY to late to start over by the time i realized the problem. I haven't watered them in two weeks, and they still aren't drying out appropriately!\

So yes I agree - the water retention mixes might be fine for larger more established plants, but I think they are terrible for seedlings.

Jeff

Whoah, I think you're on to something! I didn't mention it in my initial reply because you hadn't said yet that you replaced the windows, but I too have been suspecting that low-E windows cause damping off for years. I never ever had problems with damping off until we moved into a new house, and now I fight with it every year, despite the fact that the seedlings get plenty of sun. I've been suspecting the windows all along, but could find no corroborating evidence on the web until now!

Basically, I gave up on starting seedlings indoors, and I built myself a little greenhouse instead. I also have a few cold frames for hardening off. It's actually a better solution in the long run anyway, because I can fit a LOT more in the greenhouse than I ever could in the windows, and I don't have to worry about dirtying the sills. On cold nights I usually pull everything back inside. On really cold days I run a little portable heater with a thermostat, but I don't like to use any more energy than necessary, so I really only use the heater on occasion.

-Diggity

Here is a link that might be useful: Garden Imperative blog