heating in polytunnel

pepperpixie

ok i've just gotten a new polytunnel, don't have electricity in it, and would be too big a job to do it. Anyone know if it's possible to get solar powered heaters or solar powered propogation boxes etc?? I've had a quick look on google and not coming up with anything. Can't afford the gas heaters!!

wexford12

Why do you want a heater. if you are starting of seeds etc cover them if its very cold then they have double protection

redser7

Looked into this before and they just don't exist. Google passive heating and look into thermal mass heating, like having butts of water in them.
As above, use fleece to protect sensitive plants on cold nights.

pepperpixie

thanks for the replies, guess i'm just having a mini panic attack here, read in a book that most of my little plants should be kept at a temperature of no less than 12 degrees celsius. I landed them all out in the tunnel Saturday (had no room left in my kitchen), then sunday morning i put a thermometer out there and it was reading 4.4 degrees so not expecting any of them to survive this year. So if i get the fleece what do i do with it, just lay it over the little plants??? would this not crush them?? (sorry really am an amateur)

redser7

Yes it is a very light woven material, Lidl and aldi are selling it at the moment i think. You can lay it on in layers depending on how cold it gets. Newspaper over the top can also work.
So what plants are you talking about? Is the tunnel on your property? For half-hardy sensitive stuff like tomatoes, chillis, peppers etc. they should really be brought into the house at this time of year on cold nights.

pepperpixie

Redser7, yeah it is on my property, they were all getting a bit big so i potted them on, (they were in my kitchen) but when i potted them on they took up all counter space in kitchen & utility so had to put them outside

the plants i put out are tomatoes, chillis, peppers, cucumbers, aubergines, broadbeans & courgettes.

Think i better start off another batch of stuff probably gonna lose all this aren't i??

redser7

Well that's good news. Having it on your property means you can move them in and out as you need. Mine is on an allotment so I can't really do this. Just organise them into shallow boxes or bread trays and bring them in at night to the kitchen table, then back out in the morning once the tunnel warms up.
Those plants are the very ones you need to keep warm unfortunately (apart from Broadbeans). How are they looking at the moment? They might have been knocked back. If you have spare seed sow some more now as backups. They will probably catch up your earlier sowings.
This is the trickiest part of the year for stuff like that, shuffling stuff around on window ledges and in and out of doors. What you could do is look into heat mats or soil warming cables and run electricity to your tunnel. With that and fleece at night you can do it. Maybe make a minitunnel/propagator inside the tunnel itself for cold days/nights.
Of all those things the aubergines and peppers are the most sensitive to they definately need to be molly coddled until about May. The toms can take lowers temperatures.
2 great books for you - "The Polytunnel Book: Fruit and Vegetables All Year Round" by Joyce Russell, and "Gardening under Plastic" by Bernard Salt. I prefer The Polytunnel Book but both are very good.

redser7

Take a look at this from about 6 minutes on ...
http://www.youtube.com/watch?v=r3MG3dT1-MA

In a later video she shows that it worked well. If you cant get bubble wrap maybe you have some spare tunnel cover or improvise.

pepperpixie

thanks Redser, I actually got the polytunnel book in the post today from Amazon, gonna head into aldi now and see can i pick up some of the fleece!! The aubergines & courgettes are looking a bit floppy at the moment, they had gotten very stalky anyway. The tomatoes look very unhealthy and so far the chilli and peppers look as if they are holding their own. The broad beans are absolutely flying!!! Will watch that clip on youtube later thank you so much for your help. Checked temp in polytunnel about an hour ago and it was 14.4 in there. Think i'd be divorced if i started bringing the stuff back in at night, that was part of my argument for getting the polytunnel the "oh sure we won't have plants all over the house" conversation went on many a night!!!:D

redser7

:-) Best of luck. Well think about sectioning off a part of the tunnel like in the video clip and use lots and lots of fleece layers at night. Very important to take it off again in the morning.