Product Description

The Seedling Heat Mat increases germination success of seeds, and promotes faster growth of seedlings, cuttings and transplants. Heat mats are designed to fit under common seed flats and are constructed to be waterproof. Warms rooting area 10-20degrees F over ambient temperature and no thermostat is required. Available in 3 convenient sizes.

Product Details

• Amazon Sales Rank: #771 in Kitchen & Housewares
• Size: 48 x 20
• Color: black
• Brand: Hydrofarm
• Model: MT10009
• Dimensions: 4.00" h x 4.00" w x 22.00" l, 1.80 pounds

Features

• Increases success of seedlings and cuttings
• Warms root area 10-20F over ambient temperature to improve germination
• The only UL Listed seedling heat mats on the market!
• 6 foot power cord
• Waterproof construction

Customer Reviews

Insulate under the mat!
We are home gardeners and have tried many ways to provide bottom-heat for vegetable seed germination -- atop my always-on docked laptop was the most effective but the space was tiny. We bought a 20" x 20" heat mat and now have the right tool for the job. We set it up on a card table and found that it was not providing sufficient heat to the soil in the trays above. After an overnight on the mat, the soil surface was less than 10 degrees above ambient temperature. The room where the seeds are was 60 degrees overnight, and the soil surface in the trays was 68 degrees -- certainly not good enough for eggplant germination. I used an infrared thermometer (Raytek Minitemp MT6 here on Amazon) to check all temps. The exposed mat surface (no tray on top) was 82 degrees. I felt the surface on the underside of the card able and it was definitely warm, indicating heat loss downward. I wanted all of the heat to go up into the soil, so I cut a piece of rigid-foam insulation just slightly larger than the heat mat (22" x 22") and put it under the mat. Within 15 minutes the exposed surface of the mat was at 97 degrees and when I moved a tray to measure the temp of the mat beneath a tray, it was at 115 degrees. 2 hours later, the soil surface temperature was at 85 degrees. I am now confident the soil will get enough heat for proper germination, and I will begin using the heat mat thermostat to regulate soil temps based on the particular seeds we're starting (search the Web for "vegetable seed germination temperatures" to find one of the many reference charts available). We can also regulate temperature by covering or uncovering the trays to change the rate of evaporative cooling. We are well aware that covered soil is more prone to damping off/seedling death, which we now control with a spray of strong-brewed chamomile tea.

Well Made
This mat is well made, very durable. It came tightly rolled and did not unroll well until plugged in and warmed up it then laid completely flat. I have it connected to a thermostat, the combination is maintianing the temperature where set.

It works!
I have a tabletop greenhouse in my (unheated) garage, and I use the large version of this mat along with the thermostat controller to keep the seedlings warm. (I also add a 40w lightbulb in the winter to keep the air warm). My garage never really gets below freezing, but it can be in the 40's quite often.

The mat does a great job of keeping the bottom of the flats warm. In the spring, it gets the seedlings off to a quick start, and lets them grow without any setbacks from cool weather.

I also use it during the fall and winter to keep a constant supply of fresh garden herbs. Again, it does this quite well, although the 40w bulb helps keep the air warm.

It arrives rolled up, but within a day or so it lays perfectly flat. It seems reasonably well made, and my first one has lasted a year with no sign of problems. I am not sure how well it would do if left on 24/7, but since I use a thermostat, it is only on maybe 40% of the time during the cooler months.

Its a matter of choice, but I could do without the instructions printed in bright green on the top of the mat.

In summary, I love having seedling mats to jumpstart my spring growing, and the fresh herbs all year are fantastic. While I didn't really shop around too much for heat mats, these seem to work quite well. I suspect I could do better on price with another brand, but I didn't bother to when I bought the first one...and I will always go with a proven performer when I buy a second one.