You should be able to find a single flat size mat for about $20. If you can't find one locally check on Ebay.
Karyn

What seeds need bottom heat to germinate? I ask because my lettuce and onions have done squat on top of the fridge. I'm not using Jiffy Peat pucks on them, but the lettuce is in Jiffy peat seedling trays (peat egg carton looking things). The onions are just in vermiculite. Do they need bottom heat? I heard lettuce actually wants cool temps to germinate so after a week+ inside I moved them to the 45 degree garage.

Color me confused.

Here is a link that might be useful: Sinfonian's gardening adventure...

Seeds that suggest an optimum germination temperature do not require bottom heat to achieve the temperature. The soil in a space will after a time equal the temperature of that space. Al

Yes, as calistoga says, the use of the term "bottom heat" is really misleading and can be confusing. Most all seeds will benefit from some source of additional soil warming to speed germination but the amount of extra heat needed depends on the ambient temp in the seed starting area.

EX: In the warm house needs less than in the basement and in an unheated free-standing greenhouse needs more than in the basement does, etc. And, once sprouted, the temp needs of various plants changes drastically.

There are lots of gimmic seed starting equipment offers out there but no "special $30.00 germination tray" is required. There are many ways to supply additional soil heat depending on where you are doing your germination. They range from a sunny window to the top of the fridge or TV, to just using warm water, using shallow flats with less soil vs. deeper containers helps, heating pads, electric blanket, soil cables, used water bed heaters, etc.

Why don't you post exactly what seeds you are trying to germinate and where you are doing it and we can suggest ways to supply the heat if its needed. ;)

Dave

Thank you for the replies.

In this case I am refering to Passiflora Edulis and similar variety. They state that without bottom heat it can take 10+ weeks to germinate, versus a few days to a week with 70-80 degree bottom heat.

My house stays 73-77 degrees, but the peat pods always feel cold. What are my options?

Thank you

Cooking thermometers (I think my favorite was sold as a candy thermometer.) are rather inexpensive and some show temperatures down below 70° or so. So just get a cooking thermometer with a low range and stick the probe into the soil and read the temperature.

I have found that most seed seem to germinate best at temperatures at or near the top of the printed range.

Peat pods may make it more difficult due to their density - using a 1 1/2" layer of soil-less potting mix in a shallow pan for germinating is much easier to regulate the temps in.

But 70-80 degree bottom heat can easily be obtained on top the TV or fridge, near a heater vent, on top a hot water heater, in a cardboard box with a light bulb in it*, with a drug store heating pad set on low, and in your zone likely a bright sunny window would do the job. In addition, as I listed above, old water bed heaters picked up at garage sales are great as they come with thermostats.

*There is lots of info available on the web for making your own heat box for seed starting. All you need is a cardboard box or a plastic rubbermaid tote, a lamp cord pushed through a hole in bottom of the box, screw in a 40 watt bulb and plug it in, push a couple of dowel rods through the sides of the box to suspend the tray over the bulb.

Hope this helps.

Dave

I looked at drug store heating pads recently, and they all had some type of automatic shutoff.

If your house is between 73 and 77 degrees, heat pads with built in thermostats set at 70 degrees,would feel cool to your hand. They would be of no benefit to you. My unheated greenhouse temperature drops to about 45 degrees at night and gets up to 60 degrees during the day. If I feel my 70 degree pad in the early morning if feels quite warm, later in the day it feels cool. The pad temperature remains the same, the ambient temperature changes. Al

I've always used a soil-heating cable buried into the seedling flat(s). Models with an automatic thermostat work like a charm. They allow you to keep the greenhouse or whereever you're germinating cold, while the soil will stay a consistent toasty 72 (or so). Once germination is complete, the plug is pulled.

I've had the same cables for about ten years.

Check for a cheap Heating Mat at Walmart. Might get one for around $10.00 and those worked well for me. It's actually good when they have that flimsy cover that you can remove, as the cheap ones are vinyl underneath which can get wet without problem. :-) Carola