Overwatered seeds using covered starter kits in greenhouse

We've had an incredibly warm March in East Central IL & I started seeds on March 13 outside in my little hobby greenhouse once the night temps were not falling below 50 degrees. I used soiless starting mix and 72 hole, clear covered kits. This is my very first attempt at starting flower and vegetable seeds and nothing had come up, so I checked last evening and the only seeds that I can actually uncover and SEE were mush. I know I let them stay too wet with the covers on. I have other things I started the same way during the course of that week - petunias, tomatoes, cabbage, etc. With the tops off now and some good circulation, do you think anything has survived? I'm just sick that I've been this dumb. I bought quality seed and read every article and book I could find and they all said that too wet was always better than too dry for starting seeds. Do I assume I've totally killed everything off and replant? Can I use the same soil & hole or does the rotted seed contaminate it? Or is this just a wait and see game now on the rest? Thanks for any advice.

For seed-starting, one wants constant moisture and the usual way to achieve that is by covering the flats so that high humidity is retained inside the cover. Unless you were watering compulsively at the same time, the soil should really not have been too wet. Were you watering constantly in addition to having the cover in place over moist soil?
Germination will take longer in outdoor conditions with night temperatures dropping to 50 deg F, as compared to an ideal seed germination temperature of ~ 70 deg F (such as you'd get indoors). Easy germinators like you mention may start very rapidly indoors, but will take longer in cool conditions.
Personally, I'd wait a while but If you are convinced that the seeds have actually rotted, and that the flats are sopping wet, I'd allow the set up to dry out a bit, replant seeds, cover it again and this time, water only enough to keep the soil moist.

I think the "watering compulsively at the same time" is probably the case. I was afraid that they would dry out because the daytime temp in the greenhouse was over 80 even with the vents open. However, it is one of those "frosted" polycarbonite greenhouses so I don't think I cooked anything. But I do think I may have saturated them rather than just keeping them moist. The covers were coated with extremely heavy condensation at the beginning. I know my one "row" of lupin(e) seeds are the mushy ones and I think I had a few seeds left, so I could replant them. The rest were extremely small and mostly top sown except for the tomatoes. I did the tomatoes the most recently (On the 16th or 18th maybe) although they've probably been kept too wet also. I guess it's still relatively early but I wanted my petunias to get a head start - they were all sown during that first week also. I will allow them to "air out" a little this week-end and hopefully salvage something. Should I leave the covers off altogether now? I did saturate the flats from the bottom before planting the first time and then covered them after sowing. Maybe I didn't get all of the water out of the bottom tray and they stayed too wet from that. Thank you for your advice.

If you are going to replant the lupin seeds, scarify them first - in other words, abrade the hard outer seed coat by rubbing the seeds against a file or against sandpaper. It's the usual technique used to greatly enhance speed of germination for all hard-coated Fabaceae (pea family plants). (It can change the germination time from weeks to days.)

Hang in there. We all suffer much during our learning years of gardening and always remember that even the experts don't always agree to the right way.
Its still early in the season so you have a lot of time (in fact you have so much time you could make the same mistake twice and still have a good crop)
What I would do is dump all the planting mix in a bucket bucket and add just a little new "stuff." Don't worry about any old seeds, (one may germinate and add a later surprise) and start over. If you need more seed don't be afraid of the lesser expensive kinds.
Sow seeds according to instructions, water till the soil is "moist" but not damp and cover.
Take cover off daily and inspect to see if you have moisture to the touch. Add water if needed.
And for heavens sake, don't think you did anything dumb. I could write a book on only the stupid things I've tried in the garden.
Good luck and don't hesitate to come back with any questions

It wouldn't be so embarassing except that I used to be a florist, plus my father and my grandfather kept greenhouses. (Different sides of the family though). My grandfather ran his during the Depression and had several articles written about him in magazines because he had used some unknown heat source during the winter other than solar or something - he passed away the year I was born. My dad really didn't start his until after I was grown and moved away from home and he is gone now too so I have missed both of their expertise. Now for the questions - You talked about taking the covers off.... I am assuming your opinion at this time is that all have been kept too wet and starting over is my best option? Or should I leave the covers off to dry them out a little and see what happens next week? I'm asking because the tomatoes were planted last and might survive because they weren't kept sopping wet as long. BTW, your yarrow photo is beautiful - I have a mixed container of it that I started last year with several colors but have not seen any new growth yet, however, my lavender and catmint are sprouting in the greenhouse. I have not uncovered my mums or hydrangeas yet in the event that we have a severe cold snap. I have a new order started for one of the seed houses that are still having sales and have purchased some lower priced ones from discount stores. I corresponded with someone in OH about building a greenhouse out of old windows awhile back. Could that be you?

If the seeds have rotted then it's too late, I'd start over. If not, then I'd leave things as they are and just don't water again until things dry out a bit more. Without the covers I think you'll get too much fluctuation in moisture which will be as bad for germination as keeping them too wet, so if you have some you think you haven't overwatered then I'd leave them alone with the covers on. It's best though to remove the covers once things sprout, otherwise it's way too easy to rot the seedlings.

I HAVE TEENY TINY (Almost microscopic) GREEN SHOOTS SHOWING IN SOME OF THE FLATS! So all is not lost. I DO think that the lupin seeds are toast and possibly that whole flat because of overwatering. The rest of the rows in it were cabbage but I have more seed for that just in case. Today feels like it SHOULD be in March - high just barely reaching 60 degrees and cloudy but supposed to warm up tomorrow. Regarding the plants, should I remove the covers now or wait until more are up?

As long as the soil is moist (but not soaking wet) you could probably remove the tops. Just bottom water or gently water to the side of the plants. (getting seedlings wet can increase the chances of damping off.
I don't recall talking with anyone about greenhouses but I resently did aquire a bunch off used windows that I have considered building some type of greenhouse. I'll probably just start with a series of cold frames.
Just a note: are your seedling in a warm place? Next to a window can be a cold spot and that can drasticly effect germination time.

I did have that particular flat next to the door of the greenhouse, BUT it's been over 75 degrees and warmer here in Central Illinois for the past month and sometimes warmer during the day. I think my complusive watering caused such heavy "rain" under the covers that it just drowned them. As for the greenhouse windows - I was lucky enough to stumble across 90 windows from a gentleman who was putting new windows in his 1865 farm house. I found images of one built like what I want and have the materials for by checking google images greenhouses made of old windows and there are a lot, but this one was kind of barn gray and they'd never built anything before and I communicated with her about its construction. She was great and it has been standing 4 years now though the winters of OH. I'm HOPING to start on mine next summer. I think I have more than enough projects going outside that I didn't get finished LAST summer. I tried to copy the picture and put it on here but either I didn't do it right or it is protected. I love my little polycarbonite one but it isn't "cute" and I want one to be part of my landscape, hence the desire to build my own from windows. Try to check robomargo.com to see the pictures - you will need to scroll through to see the greenhouse but she has a lot of other stuff from old windows too.

Well, I never did get much to come up - I laid off the water until they were almost dry. I can SEE the tomato seeds sort of sprouting through the potting mix, but they are emerging so slowly! I replanted the lupins and a couple of other things that I had seed for but I STILL have nothing up. I wouldn't feel so bad except that I don't know what I'm doing WRONG in order to correct it. Are they not getting enough circulation inside the greenhouse itself? I do take the clear tops off if they seem too wet. I have my vents open on the warm days and the tops off. And now, we have freeze warnings out for tonight so I have a heater going. I AM SO FRUSTRATED. I think if I had just opened the door and THROWN a bunch of seed in it, something would surely have grown. I guess I'll get it right eventually, but it's very disheartening.

Air circulation isn't relevant to the seeds germinating. Sounds like the tomatoes are doing fine - don't worry, they'll grow at the rate that they are supposed to! Did you scarify the lupin seeds before planting?

Yes I did scarify as you suggested before replanting. I checked them last night and they have rotted in the short space of a week or so. This time I was extremely careful not to over water and yet had the same problem. Should I dump all my starter medium, sort of mix it up again and replant some things? Is it too late to try to start petunias, marigolds, etc., and have them blooming for summer? The tomato seeds are not rotten but just SITTING there in the medium. They are sold and visible through the medium but not sprouting. They've been planted for three weeks now. I am considering bringing the tomatoes inside to see if they will germinate in excellent east lighting. I figure it might be worth a shot. I plan to purchase a few more seeds and try again. SOMETHING has to sprout SOMETIME eventually!

I know you said you were careful about watering, but if seeds were rotting it's because they were kept too wet, so you might need to back off even more. As far as reusing your starter medium, if there have been things rotting in it, I'd either throw it out and start with fresh or at a minimum you'll have to sterilize it.

I have purchased some new bags of seed starter so will get rid of the old. Probably lots of nasty bacteria in the old from the seeds. I think I will dump it somewhere in my yard just in case SOMETHING surprising happens! And last time, the starter I purchased said to pour it dry into a 5 gallon bucket and add water and mix with hands (can't remember what amount of water it said to add right off the top of my head.) Should I do this differently, put the medium in the pans and then wet it from the bottom before I plant the seeds? Plant them in dry medium and THEN wet from the bottom?

It's the amount of moisture that's important, not how you get the mix wet. It's probably easier to get it a uniform moisture level by mixing it in a bucket first but be careful not to get it too wet (shouldn't be dripping wet--more the level of wetness of a wrung-out sponge).

I did mix in a bucket the first time but I think maybe I may have started the mix too wet in the first place - it was almost like very thick mud but I thought it would dry out so I didn't get too concerned. They were probably too wet too long from the beginning and then with covers on, the heavy condensation would have totally drowned them. Will try again. We are still having nights in the 40s. Do I need to run a heater at night in the greenhouse? It doesn't seem to retain much heat - it's a 6x8 kind of "frosted" poly one, even though it has a partial brick floor. Our days are 65 - 70 degrees - should I open the top vents or leave it pretty warm in there during the day? My thermometer hovers at about 80 during the day in there. Thank you so much for your help!

I've been reading your discussion and would like to add just short comment. A good way to prevent the overwatering of seeds [they only need to remain moist and not wet / because of damp off] is to place your medium in the germinating container or flat and then place that container in a larger one with warm [not hot] water and let it soak up until the top becomes moist. Make sure that the container with the water is not filled to full, it should only contain enough water to come up slightly on the side of the starter flat. Keep the water level at this height only until you notice the medium is moist on top. Never soak your medium. Then remove the seed flat from the water and plant your seed. A good rule of thumb is to plant the seed just deep enough to cover the seed with the medium. Cover the seed starting flat and allow to germinate. The important temperature that you need to keep in mind is that of the starting medium which should be at a constant 70 degrees F. Seeds do not need sunlight in order to germinate and it is better to keep them out of the sunlight until they do germinate. NOTE that if your seed starting medium cools it only take that much longer for you seeds to germinate. You have been given a lot of good advice from the other posts that I have read, Good Luck and enjoy your garden.

Thanks to all of you, especially to gardenworm - I was pleased to see a Northern "Midwest" response too. I think I will replant (tomatoes) as you suggest and go from there. Our nights are at freezing level at this time so inside germination might be my answer for a few days/week until we start to warm up again and before I need to run my heater in the greenhouse. We had such high temps in March that it was terribly misleading and we all got a little ahead of ourselves, I think. I have NEVER mowed grass in March but I mowed 3 times in March this year - in shorts and sandals no less! But we are paying for it now. The local farmers gambled and some planted......don't know yet if they are damaged by cold or not. Thanks to all of you again - I will report back I have GREEN showing safely!

I have to work from a greenhouse to start my seeds or store things in pots over winter and I never water seeds or germinated seedlings from the top of the soil, I always do it the same way as Gardenworm has mentioned, seedlings and fresh seeds don't need a lot of watering, just enough to keep them from drying out. A good way to tell there is enough water in the soil when bottom watering is to watch the colour of the soil turn darker, at this point you lift the seed container out of the water and let it drain, soon as there is no more water from the bottom of the container, place the seeds / seedlings back either under lights, into warm propagator or windowsill where ever they are to grow on. IF you water from the top, you sometimes cause the seeds to float and they all grow in larger bunches which can cause damping off. it takes practice as you go along, so don't give up, just re-sow again and take more care of the watering and light, turn the seedling every day so they don't grow bent over looking for light, by turning the seedlings they will right themselves again as they will get better ratio of even light.
Good luck Jroo73, you will get more confident as you go along and see the fruits of your labour. WeeNel.

Well, I brought my flat of tomato seeds inside to a sunny window and covered them with a black garbage bag. I figured I had nothing to lose by trying it. The seeds were sown on 3/15 and after a week inside when I opened the bag, I had about 8 little spindly guys up! (almost a MONTH from the day I planted them). They look so fragile - but they obviously need more light than they're getting in the window. What is the lowest temp in the greenhouse that they will tolerate at this stage? Do I leave them uncovered? I have clear tops for the flats but they seemed to hold in too much moisture between night and day temperature changes. (Right now, outside temps are mid 40s to low 50s at night and 60-70 during the day. And now I have sown some other seeds in the greenhouse, using the black bag method also. I was much more careful about the moistness of my starter and am hopeful of better results. I may have to bring them inside to a more constant temperature, though, for germination.