New to Forum - some questions, comments about heating mats

11 years ago

I have been starting flower seeds indoors for years and have a great deal of experience with success and failure. I wanted some information on heating mats and saw the discussion. Last year was the first year I used a heat mat but had to buy new ones this year due to losing my home and contents to a fire. I bought one mat from a trusted garden supply (too expensive) 2 off the internet, and recently a kit with mat from a big box store. On this last one I was appalled that the directions stated you should put the mat on a timer.??? I was told by my trusted garden shop that I needed the timer on the lights but that mats need to be on 24/7, which I already knew. So when I read the box, I hit the internet for answers. I have used a small enclosure off the finished part of the basement for my plant room, with grow lights timers, shelves, etc. and have had some wonderful results. When they did the rebuild I told them I wanted the same but refined. I have four outlets with a programmable timer and 4 outlets without timer for heat mats. I just started my first tray last night with heating mat, dome and light about 2" above dome, giving them 8 hours of darkness each day. I do not have a thermostat but a thermometer. My home thermostat drops to 64 while at work 5 days a week, to 67 during the night and is around 70-72 the rest of the time. So I will am hoping the mat will make up for the fluctuations. Even though I have been growing from seed indoors for years, I still need lots of help. Over the years I have heard that seeds do not need light to germinate, only heat. Others say they need both. I have always heard that once the seedlings emerge, both the dome and heat goes off. I have notes that say light should be no more than 6" above plants while others say no more than 1". I look forward to hearing more comments from newbies and veterans by joining this group. In the meantime, I just hope my snapdragons, impatiens and coleus I started last night will be off to a good start. I started later than I wanted and will be adding more tomorrow until all four mats and four hanging lights on the new plant are filled with trays. (and by the way, I freeze the seed packs before planting which shortens germination time too) Just thinking about my sad stories of losing plants from damping off, leggy plants, etc. but hope I can help others while learning more while waiting for Spring and a new garden in my newly built home. Your thoughts are appreciated regarding mats, lights, temps, etc.

Sort by:Oldest

Comments (4)

wertach zone 7-B SC
11 years ago
I don't grow flowers, I mostly only start tomatoes and peppers, but from a veggie plant starters point of view....
Some seeds need light, some don't. Read up on what you are planting.
The type of lights will make a difference in how far above. Florescent, close, incandescent or Metal halide not. In other words if it burns your finger when you touch it keep it higher.
The dome comes off, keeping heat mats on depends on a lot of things.

I have shelves above my water heater for seed starting, no lights or heat mats. When they germinate they come out and go under the lights. I have florescent shop lights and a few CFL's and I keep them close to the plants.

Cooler temps and plenty of light will keep most things from getting leggy. But you need to adjust things to what you are growing. Research your seeds!
BloomCin Zone 6b North Jersey
11 years ago
I think your home temperature is perfectly fine for most of the plants. This year I tried new guinea impatiens from seeds. They ask for 76-78 degree for germination. My house is at 70-72 in the day and probably 65 at night. And they sprouted just fine! I did put them in salad boxes and stack them close to a heating vent. So in the salad box the temp was probably higher. I consider myself a newbie who has learned A LOT from this forum. I don't have heat mat and germination has never been the problem for me. I did have damping off last year on pansy so this year I am trying bottom water. It works wonderfully so far. As to lights, I got LED shop lights from Costco this year. A big step up! They are just amazing. I only put seedlings under light. Even for seeds that require light to germinate, e.g. petunia, I don't put seed tray under light. Just near the window.
Related Professionals
Dayton Landscape Architects & Landscape Designers · North Adams Landscape Architects & Landscape Designers · Fargo Landscape Architects & Landscape Designers · Elmira Landscape Architects & Landscape Designers · Augusta Landscape Contractors · New London Landscape Contractors · Traverse City Landscape Contractors · Jamestown Landscape Contractors · Bend Landscape Contractors · Sioux City Tile and Stone Contractors · New York City Tile and Stone Contractors · Saint Marys Tile and Stone Contractors · Napa Tile and Stone Contractors · Stockton Tile and Stone Contractors · Idaho Falls Tile and Stone Contractors
arlene_82 (zone 6 OH)
11 years ago
I also consider myself a newbie - this is my third yr starting seeds indoors, and the first doing it in the cold basement. I have used a heat mat to start seeds the last 2 yrs - a smaller one that fits 1 standard tray. Once seeds have sprouted I move them off the mat. This year, I bought another mat that fits two trays. I think the petunias, coleus, and impatiens will appreciate growing on in 70ish temps rather than the 50 F ambient temp in the basement. Some things are moved off the heat once germinated, like the bells of Ireland and the Lavatera and snapdragons. I have enough light and room at the moment to fit 5 trays, with three on heat and 2 off. I don't have a thermostat and I do keep the mats on a timer with the lights - 12hrs on and 12 off. I feel that replicates avg spring temps here well: 70s in the day and low 50s at night.

I also recommend "From Seed to Bloom" by Eileen Powell as a great reference for seed starting and seedling care. I found it at my library.

Good luck and have fun with your new garden!
treehugger101
11 years ago
This is probably for a different thread but this new format has me totally confused. Thanks for bearing with me. I am growing first time this year on a heat mat - peppers and egg plant. Most of the peppers just sprouted but the egg plant and four really hot peppers have not. So do I cater to the tallest ones which have the first set of baby leaves now, take off the heat mat, put the fan on, take off the dome or wait until the last guys sprout? It sounds like the late guys will sprout eventually so I am going for option 1. If anyone has any immediate idea, I'd appreciate it. Thanks and Happy Growing!