Soil temps is what counts in germination and soil temps will always be lower than air temps without some applied heat source. How much cooler all depends on many things, type of soil, depth of soil, water temp used, air circulation, etc..

So at say 60-65 degrees soil, approx. 7-10 days. Warmer soil means faster germination. 75-80 degree soil will usually get germination in 3-4 days assuming proper soil moisture levels.

Dave

OK, I grow peppers and have heat mats with a thermostat. I guess i can dig it back out and set it up for a week or so. Thanks for the advice. I usually set it at 83 degrees for my peppers. What should I set it at for tomatos?
Bruce

My tomatoes come up in a week with no heat mat. I would dig it out for peppers but tomatoes will come up fine without it unless you are in a hurry. I usually put my tray on top of a shelf or refrigerator in a heated room and move them to the basement under lights as soon as they sprout.

Helen is right. In a hurry - heat mat @ 75 degrees as i mentioned above. Otherwise just find a warm place to set them.

Dave

PS: just for clarification, it makes no difference if they are "heirloom" varieties or not. Same for any tomato seeds.

Thanks all. Gonna dig out the mats I guess. 75 degrees?
I didn't know if the heirloom thing mattered much. But with all the crazy hybrids out there, I figured it might factor in.
Thanks all for the help.
Bruce

Bruce, I have seen more folks COOK their seeds when using those humidity domes than you can imagine. If you feel you need to use them then prop open one end to allow for air and lack of build up of humidity.

Time to germination has many variables.

The first one is seed age. With traded seeds you seldom have a clue, with purchased seeds you'll often see packed for, and some date, but that's the packed for date, not when the seeds were produced.

Heart varieties lose viability quicker than others.

Also, what specific mix did you use, some are much better than others.

Many of the better seed sites do germination tests on the seeds they sell, that's good.

Sandhill Preservation sells NO tomato seed older than two years old, which is outstanding.

Hope that helps.

Carolyn

I agree with most:

Tomatoes germinate in lower temps than peppers. Room temp (70f) will do. It will take a few days longer if it was in slightly higher temps (75 -80) . Pre soaking can help some. It will take probably a couple of days for the cover of the seed to soften in moist soil. There goes and extra delay.

I do not think variety is a factor in germination but QUALITY (age, viability) are.

SIDE NOT: Bruce,
Interestingly, I started mine 3 weeks ago. Now they are 4 to 5" tall. Another 3 weeks, they should be the right size to go out. So I think 6 to 8 weeks is pretty good pick. Yours should be ready by Mothers' Day.

Room temp (70f) will do. It will take a few days longer if it was in slightly higher temps (75 -80) .

Just the opposite. A few days shorter. It takes LESS days to germinate at higher temps.

Dave

I have the dome on but it has a 1/2" crack around the perimeter. Besides, my heat mat is thermostatically controlled so it shouldn't cook the seeds. I have it set for 75 degrees F.
The mix I used is same as my peppers which is a mix of peat, perlite and pine bark fines.
Bruce

I have the dome on but it has a 1/2" crack around the perimeter. Besides, my heat mat is thermostatically controlled so it shouldn't cook the seeds. I have it set for 75 degrees F.

&&&&&&

I understand. it's not so much that the underlying temp would cook the plants, it's that without adequate venting the humidity builds up and heat and high humidity together can kill seeds.

I'd rather see you prop up one end of the dome than to rely on a half inch crack, which IMO will not allow for good ait flow.

Just my opinion posting online since 1982 at message sites and seeing folks getting in trouble with those domes.

I started out using 8 inch permanest trays, puttig a baggie over that and propping up one end. Then went to commercial 20 row seed starter inserts and did the same.

They were placed atop the lights on my light stand, and all was well.

Hope that helps,

Carolyn

Thanks Carolyn, point taken. I will open it up a bit.
Bruce

OK, I have my mat at 80 degrees with a loose piece of plastic wrap laid over them. Should I drop my mat to 75 or 78, since I am at the higher end of the spectrum? Thanks for the helpful post, Bruce.

Plastic wrap is worse than a dome IMO. It can come into direct contact with the sprouting seedlings and lead to damp-off.

Is your heat mat thermostatically controlled or not? If not yes, 80 can cook them. I find 75 to be ideal but then I don't use domes or other covers and do have auto thermo controls.

Dave

Just the opposite. A few days shorter. It takes LESS days to germinate at higher temps.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Correct. I meant to say the opposite.

Dave, it is thermostatically controlled. Sorry, I wrote plastic wrap but it is actually wax paper. I plant in little plastic dixi type cups, and don't fill them fully with soil so they don't come in contact unless I am really bad at checking up on them. The first one just sprouted, and I removed it from the mat already while it was still curled over. That was 3 days. I would hope to have more than one sprouted by 4 days if the temps are right and the soil remains moist. Will see what happens tomorrow. I turned it down to 75 and we will see if the next batch I plant this weekend sprout any faster at the lower temp.

Hmmmm, mine are two days, I better go check :)
Bruce

Nope, nothing yet. :(

For what its worth mine were up in 8 days, no heat, no dome- just a room heater set to 68.
I was really surprised they came up that fast. I didn't even have my lights set up yet. I just hope mine have time to get big enough to set out on time this year.
Kim

Yay, bonanza day, as I had hoped. 19 have sprouted on day 4, and day is not over yet. More to plant today and tomorrow. Sooo excited to have winter over. Spring ALWAYS comes eventually, right? Otherwise my sewing rooom in going to look like a jungle in a few weeks. :)

I am always delighted at how quickly fresh tomato seeds sprout I'm my set up. I attribute that to temperature and not technique. They are in the warmest room in the house (day temps are around 75) and I put them under the lights right away, which raises soil temperatures. I don't use a heat mat or a dome for tomatoes. (I cooked them using both several years ago, as Carolyn warned.) I use an instant kitchen thermometer to test the soil and it registers about 78. 90% of my new seeds sprout between 4 and 6 days. A couple from 2011 and 2012 showed 50% germination at 7 days. I expect a few more will emerge in the second week. With this method, it's important to make sure the surface of the seedling mix stays moist. The lights can dry it out.

OK, my question has been answered. 4 days.
I just looked and 6 of the 9 containers now have at least one sprout. Thanks for all the info.
Bruce

I am very new to gardening (much less germinating) and I am happy to report that in less than 4 days (about 3.5) I have one new seedling. So exciting!

Ok, Update. I have sprouts in all 9 cells now. The last three popped since my update earlier this afternoon. So, 4 days for all 9 cells. Not every seed has sprouted however. I planted up to 6 seeds in each cell. But happy know already that I will have 9 viable seedlings out of 9.
Thanks for everyone's input. Made my first attempt at growing tomatoes from seed a success.
Bruce

I planted 3 varieties on 3/21 and more on 3/23. The first batch in biodegradable tray, the second in biodegradable cells. Both are in Pro-mix all purpose grow mix. Temp in house varies (wood heat) but is generally in mid to high 70's. Trays are in an el cheapo greenhouse from Lowes, with the door open for circulation. Soil kept moist and checked several times daily. No sprouts as of yet after 7 days....am I just impatient, or do I need to try something else?

I am soo not the person to answer this because I am extremely new (this is my first time growing anything or gardening anything) but at the 7 day mark, I have most of my tomatoes and 3 of my peppers coming up. Maybe if you are very gentle you could gently move a bit of the top and see if you have anything green under there? Again, I think you should wait for someone more experienced lol

I had 19 come up in the first 4 days and 10 left that have not sprouted after more than 7 days. All in the same cups and planting media, all planted in the same way on the same day. No idea why. I am going to plant more varieties so I will probably replant, but I never know why when the happens. I have been advised to move the soil around a bit also, and I try sometimes, but usually I can't find the seed. I wonder if sometimes they accidentally get pushing too far down into the media.

I found a couple of seeds....they haven't changed at all. Guess I'll just keep waiting!

Ok, so this year I've got germination after 5 days which is really exciting. Last year I started seed for the first time in years and sowed the seeds too deeply. It took almost 10 - 14 days before anything sprouted. So lesson learned. I do have dome but they have adjustable vents and I am now going to make sure all of the vents are open. I've never used a heat mat, just keep them in a warm room with good light. Ok, Dave, or Carolyn, what about fertilizing? What's the recommendation?
Sharon

Something that has worked well for me is baggy with paper towel. I presoak my seeds at slightly above room temp, then we go into moist paper towel, then into plastic bag and into container. Container stands on radiant heated bathroom floor. I get germination anywhere from 24 hrs to 3-4 days for majority of tomato seeds. I have done it for quite some years this way. Moisture and heat is what gives them life. Once I see white tail popping out, seed goes into 1020 tray with promix under plastic on electrical blanket. Not saying it is the way, just something one can use to have stable results in short time. I have had about 2 struggling varieties out from about 80 I planted this year.

I still have seed left......I'll try soaking with another batch!
Lindalana, 80 varieties or 80 plants? That's a lotta tomatoes!! :)
I'm hoping for a good 45 or so myself, 3 varieties!

yep, 80 varieties. Got greedy.

This post was edited by lindalana on Sat, Mar 29, 14 at 11:10

Wow! A lot of information. I have a few questions related to this. What is the best medium/mix for germinating tomato seeds? I can't plant until next year because of a move coming up shortly. Next, bet your bippy I will be doing toms. Do lights need to be turned on before germination? I know that when sprouts appear they will need grow lights.

I use seed starting medium, purchased anywhere that carries potting soil in local stores. No lights until after they sprout.

Apparently patience is key? And not my strong suit! I have 8 tomatoes sprouting this morning!

yay :)

OK, I planted my seeds exactly 14 days ago. They started popping on day 4 and by day 5 nearly every seed had popped. Now after two full weeks, they have at least one full set of true leaves. Since this is my first time growing tomatoes from seed, I am starting to think that maybe they are growing a bit too tall (getting leggy). I culled 2-3 seedlings out of each container a couple days ago leaving me with three per container. Eventually, I will go down to just one per container.
I am used to growing peppers and these are definitely more leggy than my peppers usually get. So, is this normal or do I need to get them more light. I have been raising them in front of a West-NW facing window. They get direct sun about 5-6 hours a day with indirect light about 12. I don't have any room under my Pepper grow lights but I can maybe shine a desk light on them at night and give them some extra light that way. Do I need to give them the extra light or are they looking pretty normal for tomato seedlings? I would say they are about 3" tall right now.
Bruce