Heat for seed germination

John501 · February 25, 2015

When germinating tomato seed, does it matter whether they have bottom heat (heating mat), or if the entire flat is kept in a container of the desired temperature?

TIA,
John

RayR · February 25, 2015

What matters is the soil temperature, I usually keep it at 70°F-75°F or a little higher. For me I need a heat mat with thermostat to do that since my seed starting setup is in my basement where the air temperature is usually around 60°F. You cam germinate at a lower temperature but it may take a little longer.
A kitchen or bar temperature probe is a handy way to test your soil temperature.

KarenO · February 25, 2015

Tomatoes will germinate fine at a normal room temperature without bottom heat. it will take 1 or 2 days longer but that will make no difference. Most important is to get them uncovered and to bright light as soon as the first ones are up.
KarenO

Douglas_OW · February 25, 2015

Quote:

Originally Posted by John501

When germinating tomato seed, does it matter whether they have bottom heat (heating mat), or if the entire flat is kept in a container of the desired temperature?

TIA,
John

No, it doesn't.
As others stated, the goal is to get the soil warm, usually between 75 and 85 degrees F. Bottom heat is usually the easiest way to do this, but any method that warms the soil will do. The added heat isn't essential, but some growers get better results - faster germination, higher germination rates, at warmer tempertures.

Here is an example that might answer your question:

http://tomatoville.com/showthread.php?t=9979

Jim

Cole_Robbie · February 25, 2015

I usually use a space heater and heat the room or germinating chamber. I keep having heaters with safety shut-downs in them that turns them off when they get hot. I've found I have one heater without a shutoff feature, and with the thermostat cranked, I can manage to keep the room in the mid-70's. I would prefer 80s, but will take what I can get. I am running cfl lights right above the flats, so hopefully they will warm the media a little more.

John501 · February 26, 2015

Thanks to all for the information. I have something I want to try, but got to thinking (and wondering) about this.

Thanks again,
John

AlittleSalt · February 26, 2015

I kept the room temperature at 75F. All the tomatoes germinated within 10 days. I started 62 varieties of tomatoes this way. No heat mat.

Peppers were different. 21 of 24 varieties started just fine with the 75F room temperature, but the other 3 varieties needed some help. I used an old fashioned heating pad raising the soil temperature to 90F. It did work for two, but the last one never came up.

I've read that there are certain pepper varieties that will not germinate if the pro mix is wet at all. I wish I could remember those varieties, but I do not.

Gardeneer · February 27, 2015

Seeds just need certain amount of heat/temperature. It does not matter how they get, from what they get it. So if your room temperature is 70F, then everything in there (soil, seeds, moisture) will be 70F. Bottom heating is just a convenient method. Eventually heat has to rise through the soil and get to the seeds

February 25, 2015	#1
John501 Tomatovillian™ Join Date: Jan 2015 Location: North Central Texas Posts: 4	Heat for seed germination When germinating tomato seed, does it matter whether they have bottom heat (heating mat), or if the entire flat is kept in a container of the desired temperature? TIA, John

February 25, 2015	#2
RayR Tomatovillian™ Join Date: Jun 2010 Location: Cheektowaga, NY Posts: 2,466	What matters is the soil temperature, I usually keep it at 70°F-75°F or a little higher. For me I need a heat mat with thermostat to do that since my seed starting setup is in my basement where the air temperature is usually around 60°F. You cam germinate at a lower temperature but it may take a little longer. A kitchen or bar temperature probe is a handy way to test your soil temperature.

February 25, 2015	#3
KarenO Tomatovillian™ Join Date: Oct 2012 Location: Vancouver Island Posts: 5,931	Tomatoes will germinate fine at a normal room temperature without bottom heat. it will take 1 or 2 days longer but that will make no difference. Most important is to get them uncovered and to bright light as soon as the first ones are up. KarenO

February 25, 2015	#5
Cole_Robbie Tomatovillian™ Join Date: Jun 2012 Location: Illinois, zone 6 Posts: 8,407	I usually use a space heater and heat the room or germinating chamber. I keep having heaters with safety shut-downs in them that turns them off when they get hot. I've found I have one heater without a shutoff feature, and with the thermostat cranked, I can manage to keep the room in the mid-70's. I would prefer 80s, but will take what I can get. I am running cfl lights right above the flats, so hopefully they will warm the media a little more.

February 26, 2015	#6
John501 Tomatovillian™ Join Date: Jan 2015 Location: North Central Texas Posts: 4	Thanks to all for the information. I have something I want to try, but got to thinking (and wondering) about this. Thanks again, John

February 26, 2015	#7
AlittleSalt BANNED FOR LIFE Join Date: May 2014 Posts: 13,333	I kept the room temperature at 75F. All the tomatoes germinated within 10 days. I started 62 varieties of tomatoes this way. No heat mat. Peppers were different. 21 of 24 varieties started just fine with the 75F room temperature, but the other 3 varieties needed some help. I used an old fashioned heating pad raising the soil temperature to 90F. It did work for two, but the last one never came up. I've read that there are certain pepper varieties that will not germinate if the pro mix is wet at all. I wish I could remember those varieties, but I do not.

February 27, 2015	#8
Gardeneer Tomatovillian™ Join Date: Feb 2015 Location: NC - zone 8a - heat zone 7 Posts: 4,917	Seeds just need certain amount of heat/temperature. It does not matter how they get, from what they get it. So if your room temperature is 70F, then everything in there (soil, seeds, moisture) will be 70F. Bottom heating is just a convenient method. Eventually heat has to rise through the soil and get to the seeds