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How to Use a Heating Pad When Germinating Seeds

To start your own seeds, whether for a vegetable garden or a flower garden, the seeds need a soil temperature of 65 to 75 degrees F to germinate. Many home gardeners place their seed trays on top of a refrigerator or a hot water heater to achieve warm soil temperatures. However, if you don't have room on top of either of these appliances, you can use a standard heating pad, on low temperature, to warm the soil in your seed trays.

Put a layer of plastic wrap over the heating pad. Use the type that is microwaveable, as you know it will withstand heat.

Place the heating pad on a flat surface where you will be germinating your seeds.

Plug the heating pad directly into a wall outlet, and turn the setting to "low."

Lay a thin dish towel over the heating pad.

Set the seed trays on top of the heating pad and leave until the seeds have germinated.

Heating Pad When Germinating Seeds

Read the back of the seed packet to find the correct timing for planting the seeds. Each variety of seeds will need a certain number of weeks indoors before being transplanted into the garden. Fill the seed cells with fresh potting soil. Potting soil is sterile and safer for seed germination. Plant the seeds according to the packet directions. Bury the seeds at the proper depth and pat the potting soil over the seeds so that it makes good contact. Place a drip tray on top of the heating pad and set the planted seed cells onto the tray. Most heating mats do not have variable heat settings; simply plug them in to get the correct temperature.


Be sure to check the moisture content of the soil by feeling it with your fingertips. With the seed tray on the heating pad, the soil can dry out more quickly.


Plug the heating pad directly into a wall outlet and not an extension cord. An extension cord can be a fire hazard.

Turn the heating pad off during the day if your plants are in a warm area of the house.

Insert your hand between the seed tray and the towel occasionally to make sure the towel is not getting too warm.

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