• Do you need help identifying a 🌶?
    Is your plant suffering from an unknown issue? 🤧
    Then ask in Identification and Diagnosis.

seeds trusting seedling heat mat or not

P

peplover

Hi all,

I have a few questions regarding the heat mat below. (sorry I have no photobucket account yet). The picture below is not mine, i borrowed from one of the thread in our forum. Picture's owner, please don't mind.

My heat mat setup is very similiar to the picture i borrowed below. My mat is only 10x20 and my seeds are in 2.5oz cups and I put the mat in the seedling tray and closed with seedling cover, I taped the temperature probe directly on the surface of the heat mat.

Tempurature reading from probe: 79.8f while lid is close

My questions are:

1. how accurate is the temp probe?
2. Should I trust the probe temperature, because when I touched the mat at 80F I didn't feel the heat
3. Once time I hang the probe in mid air inside the seedling tray and temp is around 80, 81f. Is this a good way for the probe to measure the temp?

Thanks all the helppppp


http://i1219.photobucket.com/albums/dd428/najamm/P1010321.jpg
 
Your readings as far as the seeds are concerned are likely not accurate with the probe taped to the mat.
It's best to always have the probe where the seeds are because evaporation can have an affect on the temperature in the seed zone, etc.
It doesn't hurt to have more than one thermometer.

~Dig
 
peplover said:
Hi all,

I have a few questions regarding the heat mat below. (sorry I have no photobucket account yet). The picture below is not mine, i borrowed from one of the thread in our forum. Picture's owner, please don't mind.

My heat mat setup is very similiar to the picture i borrowed below. My mat is only 10x20 and my seeds are in 2.5oz cups and I put the mat in the seedling tray and closed with seedling cover, I taped the temperature probe directly on the surface of the heat mat.

Tempurature reading from probe: 79.8f while lid is close

My questions are:

1. how accurate is the temp probe?
2. Should I trust the probe temperature, because when I touched the mat at 80F I didn't feel the heat
3. Once time I hang the probe in mid air inside the seedling tray and temp is around 80, 81f. Is this a good way for the probe to measure the temp?

Thanks all the helppppp


P1010321.jpg
Click to expand...


Looks like it should work although I agree thermometer with the seeds.
 
Heating mats are only very slightly warm to the touch, you're not going to feel much putting your hand on it. Also keep in mind that with those Hydrofarm heating mats the center is significantly warmer than the outer area. Mine seem to be about 5F warmer in the center than the perimeter, which is why I quit using them. Since you aren't lacking for space there I would put them all in the center or edges, whichever stays closest to 85-86F (probably the center, edges on mine seem to stay in the upper 70s-80F, but depends on the ambient air temperature in the room too).
 
Take a small pot of seed soil, water it place probe into pot place next to seeds in tray you can add a thermometer to check temp keep damp not wet, let set for 24 hr should tell you if stat is ok. have checked my mat with infared thermometer center is a couple of degrees warmer as Avon said. place plastic tray over mat and a piece of insulation on the bottom will help with evening temp
 
Thanks all for the inputs...Should I increase my center area temp to 85F so the edges can get warmer too?

Should I move the Probe to one of the edge to measure the reading?
 
peplover said:
Thanks all for the inputs...Should I increase my center area temp to 85F so the edges can get warmer too?

Should I move the Probe to one of the edge to measure the reading?
Click to expand...

85-86F is the temp you want the inside of the cups to be. You don't have that many cups, so I would just move them all to the center and try to get the seeds as close to 85-86F as possible. If the mat isn't getting up to that temp you can put a piece of styrofoam or other insulating material underneath it to get a few more degrees. You really want to test the temp that the medium/inside of the cup is and not the temp of the surface of the heat mat, they likely won't be the same. The temp inside the cups will probably be a little higher because they're sealed and the heat doesn't escape as easily.

It's kind of hard to take the temperature inside with the cup method though. I would grab an extra cup, put a little water in it, puncture the side of the cup with the probe and leave it stuck in there, then let it set on the mat for at least several hours and see what that says.
 
Avon Barksdale said:
85-86F is the temp you want the inside of the cups to be. You don't have that many cups, so I would just move them all to the center and try to get the seeds as close to 85-86F as possible. If the mat isn't getting up to that temp you can put a piece of styrofoam or other insulating material underneath it to get a few more degrees. You really want to test the temp that the medium/inside of the cup is and not the temp of the surface of the heat mat, they likely won't be the same. The temp inside the cups will probably be a little higher because they're sealed and the heat doesn't escape as easily.

It's kind of hard to take the temperature inside with the cup method though. I would grab an extra cup, put a little water in it, puncture the side of the cup with the probe and leave it stuck in there, then let it set on the mat for at least several hours and see what that says.
Click to expand...


I tray is pretty much filled with cup. I just put an extra cup with water and tissue paper to test the probe, I punctured the lid from the top and dropped the probe to touch the base of the cup..Currently temperature is reading at 80.2

Just to confirm with you again..YOU SAID TEMPERATURE INSIDE THE CUP SHOULD BE 85F? I will update the temp in the test cup in a few hours.



Thanks
 
peplover said:
I tray is pretty much filled with cup. I just put an extra cup with water and tissue paper to test the probe, I punctured the lid from the top and dropped the probe to touch the base of the cup..Currently temperature is reading at 80.2

Just to confirm with you again..YOU SAID TEMPERATURE INSIDE THE CUP SHOULD BE 85F? I will update the temp in the test cup in a few hours.



Thanks
Click to expand...

Yeah ~85F is considered the ideal temperature for the seeds to be for quickest germination. You could try placing a piece of styrofoam under the heating mat to get the temp up a little bit. You should have very good results if you stay at 80F though, that is a pretty good temperature and will certainly get the job done.
 
That's the same mat I use - and with a tray and dome it stays about 81F inside. I get quick germination with most seeds. Be careful with any supplemental overhead lighting because that will raise the heat level significantly under a dome. IMO, anything over 85F is too hot. 75F to 85F is a good range.
 
It seems that you have a high concentration of moisture in the cups, , are there air holes in the lids? High humitity/ no air circulation can cause damping off to your seeds/seedlings. Why not use seed flats with a premium starting mix on your mats? Less handling = less transplant shock.
 
PIC 1 said:
It seems that you have a high concentration of moisture in the cups, , are there air holes in the lids? High humitity/ no air circulation can cause damping off to your seeds/seedlings. Why not use seed flats with a premium starting mix on your mats? Less handling = less transplant shock.
Click to expand...


No, there isn't any hole in any cup. However, I open them everyday let to the nasty smell air out for 30sec

This is my first time growing seeds in heat mat, very noobiest about how to get things done properly plus I have a very limited budget so.

test probe is seating around 81.5 - 84.0 F.

Thanks for all the inputs.
 
You must log in or register to reply here.
Back
Top