pointer80
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Location: northern Michigan

Need advice on seed starting dilemma

Need some advice on my seed starting situation. I have a portable greenhouse set up in my workshop where I am starting my seeds. The shop itself stays at least 40 degrees. Inside this greenhouse I have a seed starting table with t-12 lights and heat mats. Around the table I have wrapped a tarp to enclose the whole set up and have a little heater under the table that is keeping the setup about 74 degrees and at night with the lights off around 67 degrees. The soil is staying about 77 to 80 degrees. So far I have onions, leeks, eggplant, and peppers just staring to sprout (it's only been a week). My dilemma is that I need to get my tomatoes started and I am short one heat mat plus the one I just ordered that was supposed to be here today is delayed until end of next week. I was going to take the one mat out from under the onions and leeks which should be fine right considering they are cool weather crops? But I don't know what to do with the one flat of tomatoes? Should I plant them and run without a heat mat until it arrives or should I put that flat in the house for a few days without lights? or just wait to plant when heat mat arrives? right now I am about eight weeks until plant out time. Thanks everyone in advance.

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applestar
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Tomatoes will germinate at 75-80°F no problem. Viable fresh seeds shouldn’t take more than 5-10 days at latest.

New Tomato seedlings will do best around 70-75°F daytime and 65-70°F night time. Once 1st set of true leaves open up, they grow stockier and sturdier at 55-65°F.

Onions and leeks don’t need any heat at all and seedlings will grow fine at 45-55°F

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MoonShadows
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My tomatoes are already germinating in my greenhouse with night time temps in the upper 40's - low 50's, and with very few sunny days the past two weeks the temps are running in the upper 50's - low 60's during the day. I planted the seeds less than two weeks ago. I never use heat mats, mainly because the cost would be prohibitive for all the seeds I have planted for vegetables and flowers (over 600). It may take a little longer for germination, but I still get good germination rates.

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applestar
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Yep - it’s easy to forget when you CAN get them to sprout within a week, but typically, most seeds will sprout in 10-14 days at “natural” temperatures, and could take as much as 21 days when at cooler (but still viable) temperatures. The trick in this case is to keep them watered evenly without drowning or drying until they sprout, and best if you have automated plant-and-forget kind of well-designed set up.

...just as a comparison, if you are doing micro-managed germination/sprouting techniques like mine to minimize space, where the tiny growing media volume dries out quickly, you do want them to germinate/sprout quickly.... Also, if you are short on time, it’s better to find out more quickly that seeds you started were a “dud” in some way so you can start over with fresh seeds.

It really depends on how you start them so try different ways/techniques until you find the method that suits your space/time/lifestyle, etc.

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MoonShadows
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Location: Stroudsburg, PA - Zone 6a

You are so right about the watering process. I check them 3 times a day and only add enough water to moisten the soil down as far as the seed is planted rather then "watering" the container. Once I see sprouting, I increase the amount of water slightly, but don't "fully water" until they are established.

SQWIB
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You only need heat mats for germination.
After gemination, remove the tray from the heat mat.

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rainbowgardener
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Everyone has their own way of doing things and you have to figure out what works for you. I do all bottom watering for seed starting except when there are seeds that require light that are just sitting on top of the soil, I also sprinkle them, to be sure they stay moistened until they sprout. And I leave things on the heat mat at least until they have one pair of true leaves, sometimes two pair. But then I do take them off. I have done side by side comparisons and they do get to true leaves quicker on the heat mat.

pepperhead212
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Here's something that I do with pepper seeds (which I'm sure you could do with tomato seeds, as well), that I started back when I grew a LOT more peppers than tomatoes, and I didn't have enough "warm areas" to put all of those trays! One tray would start enough seeds to fill 3 trays, and I'm sure many more.

Here's a photo of the tray that I would use, which has 20 strips in it, about 1" deep:
ImageDSCF1068_zpsu67mqfap by pepperhead212, on Flickr

I put vermiculite in it - the only thing that I use vermiculite for, as the roots don't get tangled in it quickly, and the seedlings pull right out, plus it holds moisture - about 3/8" short of full, then moisten all of it. Then, I put the soaked seeds in each row - when I have more than 20 varieties, which was almost always, I use the rows for two varieties , with a toothpick in the middle. I try to put the seeds a half inch or so apart, then I put another 1/4" of vermiculite on the top, and moisten all of it, then put a cover on the tray. Then, I wait for the seeds to pop up! When they are just popping through the vermiculite, I dig them out with an olive fork, and transfer them to the pots. There are always a bunch of extras, and for the ones that don't germinate, I take some of the similar types, to fill the pots I had marked for the ones that I won't have. I just have to remember to re-mark the pots! lol

I put this up on a griddle on my range, which has 4 pilot lights under it a few days before planting the seeds, and tweak the levels of the gas, to get the temp in the vermiculite around 90º. This was my original heat mat! lol The back is cooler, which I use for tomato and eggplant seeds, in another tray, but one with small pots.

pointer80
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Joined: Sun Mar 24, 2013 1:50 pm
Location: northern Michigan

Thanks everyone, Great information.



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