heated area of polytunnel

[robert0881]

im wondering if i can make an area that the soil is heated that i can plant directly into?
ive seen various under ground heating mats but there are so very expensive for a very small area. im wondering could i put an old electric blanket a few inches under the ground? its washable lol not that its even going back on a bed. i mean if its washable then it should be waterproof? soil warming cables can they be put directly into the ground. most places recomend making an area that heated then placing pots etc on top. i want to plant seedlings directly into a heated area of the ground.

thats for your help and advice

[Two_Sheds]

It would be cheaper and easier to get an indoor heated prop. Start your seeds off, when they are germinated they can go into cooler conditions.

What are you trying to start?

[Snadger]

Interesting scenario! Must confess to never having used an electric blanket at any time
Are they 12 volt, ie is there a small transformer that plugs into them? If so. I would say no problem as long as you have a weatherproof exterior socket.
If they are 240 volt I would forget it as you only get one chance with this voltage and a few early veg just aren't worth it.

I'm sure we've got a few sparky's on here who will put you to rights though

[Lovage]

I wouldn't risk the electric blanket - you can get soil warming cables of all sizes.
For a growing bed the cables don't need to be as close together as for a propagator so they can cover a larger area
Alternatively you could try the old way of making a hot bed with some rotting manure to provide the heat. In 'the old days' gardeners used all kinds of trchniques to get crops out of season for the big house
Let us know how you get on