Seed Starting!!

I mostly start my seeds indoors so the following information has been gathered by reading various forums and researching on the web and not from actual experience. 

The soil temperature of the seed starting mix is the important temperature that controls the actual germination of the seed so you should be ok as far as germination goes.

Sliding the seed tray over under the grow lights will really not make much of a difference as far as air temperature.  I do not know how much heat your grow lights generate, but my T-8's and T-5's do not generate enough heat to change the air temp around the seed trays.  Some gardeners have made grow tents around their seed starting trays if air temperature is too low.  Unless the air temps are below freezing, I think the plants will survive but will not grow much unless kept warm enough.  What I did one year when I put my seed trays on my porch was to cover the shelf with plastic over the lights and then put a slow cooker inside the plastic to keep the temps a little warmer.  You could put your heater near the plants and that may keep the area warm enough to grow your plants enough to get sizable transplants.   But doing the slow cooker method may lead to too much humidity if you are not careful.

Thanks yolos.

camprn wrote:

IillkkKathy GizziSo, I planted all of my seedlings on Wednesday, and to date, I see a whole lot of nothing!  I had hoped to see at least a sprout or two by today.  No such luck!

Did you plant seeds? What kind?

Brian, I have never germinated in a fluctuating temperature indoors, outdoors of course fluctuates wildly!  But these charts posted by Camp should give you an idea of what to expect.  I think it depends on what you are trying to get going, some things are more tolerant of the low temps than others.

I for one will not do spinach indoors again.  Mine has germinated beautifully, but bolts super early once transplanted.  Seems to need the cold to gently ease into being!

Thanks Scorpio.  Those charts are great.  I glanced at the top when I posted intially , but that bottom one gives me the info I need.

Here is a website that has a table for soil temp and air temp.

http://www.growgreatvegetables.com/plantinggrowing/germination/

I am pretty sure that the chart posted by Scorpio is air temps and if you are using a heat mat, then soil temp would be a more accurate chart I THINK.  Although it looks like there is not much difference when using the soil or air temps charts.

I start in my garage too but have a heater in there and try to keep it at least 65°

I start off the seedlings on a heat mat and have a thermostat to control the heat mats, I usually pick a temperature that accommodates the seedlings being planted, sometimes they are different temps and I have to compromise. No light is needed at this time so new seed starts may be covered with something opaque before sprouting, if I have some sprouts under the lights already.

Just know that without a thermostat, the mat will only increase the temp 10° above the ambient temperature, so if your garage is 50° the mat will go no higher than 60°

The thermostat only has one probe and goes into the soil of one of the trays and this will control the temps for all of the trays, one caveat to this approach is, if you use a dome on the probed tray, heat output will be different in the other tree trays.
Its best to start seedlings without a dome if possible.

Here is my setup,




Storage








Timers and thermostat.


Sometimes I use domes sometimes I do not, but only to germinate. (old trays)



I will take the seedlings off of the heat mat after about an 80% germination rate and place in another tray (no heat mat) about 3" under the light. If they are left on the heat mat, they get leggy.

Last year I treated myself and picked up some sturdier trays




I have a fan that cycles twice a day to sturdy up the seedlings.




I have had success with Rockwool also.






I have found that planting each species in groups in seed tray cells cut up works best because of different germination times, each cell gets three seeds.




I have also had luck with broadcast seeding and thinning to individual pots.




I sometimes broadcast seed stuff like my marigolds in milk cartons and  those rotisserie chicken containers from Sams.









I made this last year and never used it, I may try it this year, I made this so each individual plant can come off of the heat mat and put under light as soon as they germinate. I think I may do my pepper starts in here.




I started with solo cups then purchased some sturdy cups that can be run through the dishwasher each season.






Thinning is the hardest part for me, since I cant bear to kill anything that grows, I stock up on used solo cups, get out he soldering iron and pop in a few holes then pot up everything and give them to a bunch of folks, I use a different color for each person.




With the new cups I get 21 of the smaller and 18 of the larger per tray so thats about 116 plants for 6 trays.




Last year I got a bit overzealous and found an area to grow another 40 or so plants. Just bear in mind that you are only limited by your own creativity.




Yep, in the ceiling of my workshop, sprouted seeds go up here and there is a timer for the light and a fan. 6000k led bulbs





Hope this helps!

Forgot to mention that the light is a modified shop light.

It has 10 bulbs (4 fluorescent tubes) (4 led tubes) and (2 led strips)

A few screws, some scrap metal and JB Weld and I was able to get a spread of light the full width and length of 4 trays.

SQWIB ... wow!!!  That is quite the setup. Thanks for sharing. 

trolleydriver wrote:SQWIB ... wow!!!  That is quite the setup. Thanks for sharing. 

You could sell tickets and hold seminars!  WOW!

Whoaaaaaaa!  Sqwib! That’s great! Whoaaa (golf clap x 3).  I learned like 5 things from that one post.  It also made me think of about 10 more questions .

GoodNESS! That's a terrific set-up!

Nothing like sqwib, but have 1 square of green and 2 squares worth of yellow onion seeds starting.  I planted half of them today and the other half last Saturday.  The set I started last Saturday are starting to peek through now.  Tips or suggestions welcomed!

Nice job, both of you!  Makes me want to hit the catalogs, and get my plan on!

I have the large viagrow heat mat.  I am wondering if it is functioning properly.  I realize it’s not supposed to be hot, but it’s barely warm to the touch.  If I lay my hands flat on it for a few seconds I can feel that it is warm, but barely.  Is that what it’s supposed to feel like???

From what I understood is that the mats will only heat 10   degrees above ambient temperature.

From their website...
[size=31]Warms root zone 10° – 20° above room temperature
• Speeds germination and encourages strong root growth
• Fits snugly under a standard size seed tray
• High quality, water resistant construction
• Weight: 1 lb[/size]
[size=31]Place the Viagrow Seedling Heat Mat on a flat, dry surface and plug the cord into any 120V outlet. Place the seedling tray directly on top of the heated mat.  For best germination results, place a propagation dome over the tray and keep it under T5 fluorescent lighting (approximately 300-800 foot candles.) Direct sunlight or high HID lights may be too intense for seedlings.  As a general guideline, seedling and clones grow best with temperatures of 70-80 degrees and humidity range of 50%-60%.  Please be sure to research your particular plant as temperature and humidity requirements vary for different species and hybrids. The 20.5″ x 8.5″ Heat Mat is 18W.[/size]

Thanks sqwib.  I’m having trouble wrapping my head around the fact that the mat warms the area 10 degrees above the room temperature.  I guess it’s possible, but I cant figure out how the mat knows what the temp in the room is and how it knows to only be 10 degrees hotter than that. ???

Brian I agree, thats why I don't trust them and use a thermostat.

Its a bit pricey but figured it was worth the piece of mind.

SQWIB wrote:Brian I agree, thats why I don't trust them and use a thermostat.

Its a bit pricey but figured it was worth the piece of mind.

Do those connect to all seed heating mats universally or do I need to search for one that goes with my specific mat?  How much are they approx?

brianj555 wrote:

SQWIB wrote:Brian I agree, thats why I don't trust them and use a thermostat.

Its a bit pricey but figured it was worth the piece of mind.

Do those connect to all seed heating mats universally or do I need to search for one that goes with my specific mat?  How much are they approx?

The thermostat has a 3 prong 120v connection so the mat plugs directly into the thermostat.
What I do is plug a multi outlet bar into the thermostat then plug all 4 of my heat mats into the multi outlet.
The thermostat is a bit pricey at about 35.00.

I forgot to add that, the thermostat has a probe that goes into the soil to read the temperature

II found this one.  Viagrow makes it so I’m assuming it will work.  I haven’t decided if I want to spend the money though.  I’ve had a lot of funds go out with my first spring planting coming up.  (Seeds, pvc + fittings for treliis’, trellis netting, heat mat, grow lights and MM to fill my second 40 cubic foot bed) The good news is those are mostly expenses that aren’t recurring, so I might wait until later to get the thermostat.

Anyone use vermiculite on top of their seed starting median?  My onions aren’t booming like I hoped ( could be the seeds, I bought them
From Home Depot last year when I had no clue about anything   Other than onions, carrots and romaine lettuce I bought all new seeds for spring ) so I did some reading and saw a couple suggestions about topping with vermiculite.  I figured I would see if any of you do that or had thoughts on it.

brianj555 wrote:Anyone use vermiculite on top of their seed starting median?  My onions aren’t booming like I hoped ( could be the seeds, I bought them
From Home Depot last year when I had no clue about anything   Other than onions, carrots and romaine lettuce I bought all new seeds for spring ) so I did some reading and saw a couple suggestions about topping with vermiculite.  I figured I would see if any of you do that or had thoughts on it.

I have used fine grade vermiculite to cover seeds that were planted in cell packs and also outside.  Usually smaller seeds such as carrots.  It works well if used to just cover where the seeds were planted and not all over the square.

I could def see how that might be effective outdoors directly over the very small seeds.     I am starting the onions in the small packs (72) per tray.  (See my new avatar pic) I sprinkled 4 or 5 on top of moistened seed starter mix and then barely covered them.  On a couple 6 packs I only used a thin layer or course vermiculite to cover and about half the tray has a light thin cover of seed starter with a thin layer of vermiculite over that.  The other half only has the seed starter as cover.  I guess we will see what happens.  The yellow onions seem to be germinating better than the green.
The yellow onions out of the tray were started 12/23.