[pepsi100]

What would you use to heat a mini greenhouse ?
Just for seeds in a couple of trays
Just to give them an early start in the spring
I was thinking tomatoes
Never tried seeds before though, usually get plants from the garden center

[jaxter]

I think the mini greenhouse would be difficult to heat, mine are sown and kept indoors near the window in a spare bedroom.

[pepsi100]

I would have put a 100 watt bulb in there, just use a coloured one, at the bottom (heat rises)

But you cant buy them any more

[Yorkie]

I agree with jaxter - the plastic is so thin, and they have no insulation, that it's probably not worth trying (and any heat source might melt the plastic if it's warm enough to actually have an impact and it comes into contact with the plastic).

Edit to add: I've just seen your other thread. I had assumed your thread here was asking in relation to one of those thin transparent plastic mini greenhouses that has 4 shelves and space for 3 seed trays on each. If you've got a more robust greenhouse made out of wood and twin wall polycarbonate, as I think you've mentioned on another thread, then the risk of melting is obviously far less.

But heat is still likely to cost a fortune, and/or could cause lots of moisture and thus mould or damping off risk (e.g., if you went down the paraffin heater route).

[Nobbie]

What about heating mats that you sit under the trays. Only about 20w, so not to expensive to run. You can also get under soil heating cable for larger areas. I’ve inherited my dad’s system, but haven’t used it yet.

[pepsi100]

Nobbie
Thanks
Yes I had forgotten about heating mats
I saw them on special in my local garden center a week or so ago, might pay them a visit

[Snow]

I use heating mats to germinate my seeds indoors. They work great, just a couple of cheap ones from amazon. I have a temperature controller from homebrewing and I use that with the mats to bring on peppers and tomatoes in early spring, I grow them under lights in my garage as seedlings. Set the minimum temperature to 12c and that keeps them nice and stocky for planting out in may.