Seedling Heat Mat Recommendations

ninnymary

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I have some grow lights that are 4' and I'm now looking into heat mats. I've only checked on amazon and there are 2 basic ones. One is $9.99 and the other is $11.39. They both have good reviews and some awful ones. Some recommend getting the thermostat controller but I really don't want to invest more money.

Do you have a favorite that you recommend?

My grow lights will be on top of my washer and dryer in the laundry room. It is located downstairs which for us is ground level. There is no heat down there but it doesn't freeze. I would say the temps get in the high 40s, lows 50s at night.

Mary
 

thistlebloom

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I bought a propagation mat last year that worked well. But I don't think you'd like the price, it wasn't inexpensive.

I did find that I over estimated the area I'd need. Mine is 20x40 and I probably could get away with half that. There was a lot of unused space on it.

Once things are up and have their true leaves I took them off. But that was growing in the dining room which averages temps in the 60's. Most, if not all, of the mats I looked at said they raised the temperature about 5 degrees above the ambient temp of the room.
I started all the peppers and tomato plants for the kids class on it.

I'm planning on starting a bunch of flowers for clients this year, so maybe I will need all that room after all.
 

ninnymary

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Thistle, the size I want that would probably be sufficient for me is 10"by 20". Yeah, I read about that 5 degrees also. But then some said they were heating to 75-80. So I'm all confused.

I suppose I could move the set up to my dining room but that room is still on the cool side. We have our front rooms on a different zone. Much cooler than our bedroom, kitchen, bathrooms zone where we spend most of our time.

Mary
 

thistlebloom

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The temperature that counts when you're germinating is the soil temp. So 75-80 degrees of the soil is probably what they meant. Mine heated my soil to about 75 if I remember right.
It's just going to have a harder time doing that if your room is 50.

You can help raise the temperature of your soil passively if you can cover the seed tray, or what I would do- put it in a clear box, like a sweater box* and put the lid on loosely so there is a constant air exchange. That will make a more protected environment and help keep your soil warm.

*on top of your heat mat
 

Nyboy

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Mary I paid $25 for mine never used have no idea where it is. With a electrical device that will run nonstop even if no one home think safety. Cheapest not a deal if it stats a fire.I would look more toward safety features like automatic turn off if to hot.
 

ducks4you

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Mary I paid $25 for mine never used have no idea where it is. With a electrical device that will run nonstop even if no one home think safety. Cheapest not a deal if it stats a fire. I would look more toward safety features like automatic turn off if to hot.
Always a good idea, BUT, I have my seed starting setup in the basement on a wire rack shelving unit. The basement has a cement floor. I don't worry about my grow lights or my heating mats, which, if you buy them retail run $25.00
I bought mine retail on clearance and paid less.
I DO use a timer for my lights. The cheap timers where you push down on the circle last a long time.
We are celebrating my birthday with gifts next month. I need a new coffee maker bc the other one was spilling 12 cups of coffee all over my counter and the cheap replacement doesn't have a 2 hr auto shut off. My solution was to buy a timer for it, so that it can replicate the start before I wake up and then turn itself off stuff. Btw, the one spilling the coffee everywhere was a Kitchen Aid ($100.00)
DON'T BUY IT!!!
This is the one that I want:
https://www.amazon.com/Hamilton-Bea...me-20&linkId=7fd070ee47945cbceeb94cd927100fb7
 

Ridgerunner

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I cannot help you with grow mat selection Mary. In Arkansas I made my own heating box out of wood, lined the inside bottom and sides with aluminum foil to reflect heat, and used an old string of Christmas tree lights for a heat source. I regulated the heat by the number of working and burned out bulbs I left in the string. I got rid of that when I moved.

I'm not planning on starting any seeds down here this year, it will be a learning year. But I have my eye on a certain closet where I could install a 2' grow light and use a heating pad for heat. With the grandkids here a lot and a dog I don't trust I want it someplace secure.

I agree the soil temperature is what is most important when it comes to germination. I think you are starting peppers. I'd suggest at least 70 degrees for those, 75 or 80 would be even better. I don't think that is too warm for anything else you are likely to be starting, you will probably see some sprout really fast. I have a thermometer I can stick the probe into the ground to get a reading.

I would not want a heating pad that automatically shuts off. That would defeat the purpose of trying to keep the starting mix warm. I'd look for a specific grow mat designed for that specific job. Those are probably as well protected against spilled water as you can get. I'd watch where I put the plug-ins especially if you use an extension cord. Put them high where you wont spill water in them.

I don't know how you regulate the soil temperature without a thermostat. I guess you could put a dimmer switch in the circuit but I'd prefer one built in. I would not want to buy one without a regulator. Some things are just worth the cost.

Moisture is important when sprouting seeds but if it stays too moist you can get damping off. That's where a mold or fungus grows around the soil line and rots the stem of the plant in two. Once they sprout the surface of the soil needs to stay pretty dry. Until they sprout it should be moist. When I first plant the seeds I put a clear plastic cover over them to keep the moisture in and keep them from drying out. After enough seeds sprout I remove that cover to let it dry out. After that it can be a good idea to water from the bottom or find a way to water them without getting the soil surface around the plants wet. Steve gave a pretty good description of how he does that, I consider him a pro.

I got a small fan so I can direct a light breeze across the started plants to dry them out and stop damping off. I think it helps with hardening them off too. I could not find one local in the winter, they stock those in summer.

Use a sterile starting mix. The spores that cause damping off can be in the air but are often not around. Do not give them a head start. You don't want weed or grass seeds sprouting in there either. And carefully clean and sterilize your starting stuff after you use them.

I think those are the high points. Good luck!
 

catjac1975

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I have some grow lights that are 4' and I'm now looking into heat mats. I've only checked on amazon and there are 2 basic ones. One is $9.99 and the other is $11.39. They both have good reviews and some awful ones. Some recommend getting the thermostat controller but I really don't want to invest more money.

Do you have a favorite that you recommend?

My grow lights will be on top of my washer and dryer in the laundry room. It is located downstairs which for us is ground level. There is no heat down there but it doesn't freeze. I would say the temps get in the high 40s, lows 50s at night.
I have one that looks like this but is much larger. It is pricey but the first one I had I think lasted 20 years. I also have the cheap ones that fit 1 12 X 18 tray and they are OK. But I have had some fail. The one with the wire cage under it is a good product. When I am just starting seeds, and it is quite cool at night, I drape plastic over it and it really holds the heat in.I did not have to do that this year as it hasn't been that cool

Mary
 

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