Row by Row Episode 237: How to Use Heat Mats
Left Continue shopping
Your Order

You have no items in your cart

You might also like
From $2999
Show options
From $399
Show options
Row by Row Episode 237: How to Use Heat Mats

Row by Row Episode 237: How to Use Heat Mats

What is a heat mat for plants, and exactly what does it do? Heat mats have one basic function which is to gently warm the soil, thus promoting faster germination and strong, healthy seedlings. Most seeds germinate best in temperatures between 70 and 90 degrees F. To germinate, most seeds need waterair (oxygen), and warmth to break dormancy. There are exceptions, but most seeds do not need light until they have sprouted. In many climates, temperatures aren’t consistently warm enough to germinate seeds, especially in late winter or early spring, prime seed starting times. Keep in mind that damp soil is cooler than the air temperature, even in a warm room. You may be advised to put seed trays in a sunny window, but windows aren’t consistently warm in early spring and they may be very cold at night. Heat mats, which use very little electricity, produce gentle, consistent heat. Some heat mats for plants even have thermostats to adjust the heat. The idea is to provide the right amount of warmth for the particular type of seed. Work off of ambient temperature. The most important tip is to be sure to get a thermostat attachment. This may be an extra purchase unless it’s included as a set. The whole point is to be able to warm your soil to a specified, consistent temperature to make the seeds sprout. Without a thermostat to regulate things, some of these mats will heat way too hot. The one I tested recently went just beyond 112°F (44°C) when I left it running. That not only dries out the growing medium but wipes out any emerging seedlings.

Frequently Asked Questions

How long do you use heat mats for seed starting? Heat mats, if needed at all, are useful for warming soil during the germination process only. They should be removed after several seeds have sprouted to avoid overheating the seedlings. Seeds sprout at warmer temperatures than their seedlings can cope with. Can heat mats harm seedlings? Yes, heat mats can harm seedlings by drying out the soil or new growth. Only use a heat mat with a thermostat to ensure you can regulate the temperature. Seeds have minimum and maximum growing temperatures. When too low, they won’t sprout.  Can I use grow lights instead of a heat mat? No, a grow light does not act like a heat mat. Grow lights provide light and heat mats provide warmth by contact. Heat mats are used to help seeds sprout faster. Once sprouted, grow lights provide the light needed for seedlings to grow.

Hoss Germination Mat (100 Watt)

$74.99 Our Hoss 100 Watt Germination Mat provides constant temperature to seed starting trays for germinating seedlings. 20.75″ wide x 48″ long. Large enough for our 162/338 Cell Seed Starting Trays or 6 of our 24 Cell Seed Starting Trays. UL Listed safe.

Hoss Germination Mat (17 Watt)

$29.99 Our Hoss 17 Watt Germination Mat provides constant temperature to seed starting trays for germinating seedlings. 8.875″ wide  x 19.5″ long. Will fit two of our 12 Cell Seed Starting Trays or one of our 24 Cell Seed Starting Trays. UL Listed safe.

Hoss Germination Mat (150 Watt)

Hoss Germination Mat (150 Watt) – 60" x 21" MASTER MAT | $149.99 Hoss Germination Mat (150 Watt) – 60" x 21" ADD-ON MAT | $129.99 Our Hoss 150 Watt Germination Mat allows you to connect additional mats through the daisy chain feature. Each mat is 21″ wide x 60″ long. Connect up to 3 ADD-ON MATS to the MASTER MAT. ETL Listed safe. MUST USE with our  HOSS GERMINATION THERMOSTAT sold here.

Watch the Full Episode on Youtube

Leave a comment

Please note: comments must be approved before they are published.