Do you need heat mats under your seed starting trays? It depends! Here's what you need to know about seedling heating mats and when to use them!
You should only use a heat mat for seed germination under heat-loving crops. Most seed packets will give you all the information you need!
Once the seeds germinate and you can see growth, remove your seed tray from the heat mat.
You do not need a heat mat to start most seeds. Cool weather plants don't require a warm environment to sprout, and will actually suffer if placed on a heat mat.
The best heat mats are the ones that have a digital thermostat that allows you to set it at a consistent temperature.
I'm using self-watering seed trays, and the mat underneath provides enough heat to warm up the water reservoir and keep the temperature of the soil at a consistent 72 degrees.
If you have older fluorescent bulb grow lights, they may generate enough heat to increase the temperature of the soil slightly.
If your home has a heat vent close to a sunny window, placing your seed tray next to the vent might help.
Believe it or not, the top of your refrigerator is one of the warmest spots in the house.