Electric Propagator

Hi Folks. Last year near end of season I purchased a brand new parasene 3-in-1 for £20.A bit flimsy compared to my smaller one but at least it is thermo controlled should I need it.
No instructions but I have read you need to put medium in bottom first, water the medium and then when medium is warm place trays in.
Not sure what medium is best as I have read various info. Some say normal Sharp Sand, Horticultural Sharp Sand and even Gravel but not Peat, not that you can get it anymore!
Any info on what you use please.
Thank you

 

Hi

I use capillary matting , then sit the trays etc on this easy to keep moist and to check if you have added too much , thats my way I know others use sand etc but I found heat disputation was not even with my mine (Ward).

Spruce

 

One of these for £20 - sounds like a real bargain! http://www.amazon.co.uk/Parasene-3-in-1-Propagator/dp/B005HDI9D0

I use the capillary matting that came with my Sankey propagators, and also use it in gravel trays under my growlights so I can up the humidity in my growlight box.

 

Hi All.I have ordered some of the better quality capillary matting for propagator.
The Parasene 3-in-1 I got from an elderly couple who moved house and got the propagator as a present but they already had a large one so did not need it,hence £20.

 

Got my 20yr old Jemp propagator still working and the medium is damp sand in the base to spread the heat out evenly.
Now set on top of a box made up of old fence panels cut to size so as to raise the height of the propagator up to window height.
Cost me £28.00 then so no idea what they would cost to replace this model.
Holds two full sized trays with their respective covers.
Also has a thermostat too.

 

I hear a lot of people talking about using a layer of sand or some such to even the heat in a propagator. But my first thought is that sand (or anything else) is a very good insulator, so you would lose a lot of the benefit of the heat. Wouldn't the soil in the trays be sufficient to even the heat?

 

Here's some thermal conductivity figures; the larger the number, the better the conductivity. I've included a link to a site giving data on a vast number of materials.
One disadvantage that I see in using soil in a propagator, as opposed to in the pots in a propagator, is that it is more likely to grow mould and/or harbour diseases. I use a mixture of sand and perlite and keep it well watered.

Sand, dry
0.15 - 0.25
Sand, moist
0.25 - 2


Sand, saturated
2 - 4
Soil, with organic matter
0.15 - 2


Soil, saturated
0.6 - 4
Vermiculite
0.058


http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html

 

Hi Dave - nice to see some figures. Its a good point to make - to keep any sand well watered.

When I first bought a heated propagator, in my naivety - without thinking , I assumed that all the inside of the propagator would be at a constant temperature. However I did some experiments and found that the top of the small pots, I use for growing seeds, was about 10C colder than the bottom. On reflection, its logical that if the heat is provided at the bottom and lost from the top there will be a temperature gradient.

So it might be worth remembering, as the thermostat is at the bottom, the seeds themselves could be at a lower temperature than you think. And the thicker the layer of sand the lower the temperature.