Covering a polytunnel - does it have to be a warm day?

[amandaandherveg]

I ordered a 28'x14 polytunnel and now have everything built and ready to go (including aluminium base rails). However..... for the last two weeks I've been trying to fit the polythene cover but it's sat around 7-9 degrees and has rained every day. This week there's a few dry days forecast with temps around the 13-15 degrees. What would you recommend - wait for warmer weather (it may not happen) or just go agead and cover it?

[woody21]

Go ahead and get that cover on! light rain and showers are fine just not so nice to work in.

Dont underestimate even a small breeze! so be prepared for it and get a few extra pairs of hands to help hold things tight, my 20x10 tunnel was hard to hold onto with just a light breeze once half over the frame and i had 1 person helping me.

Well worth getting it covered as soon as you can as even with the rubbish weather most plants in my tunnel are still growing quicker than i expected.

[amandaandherveg]

Thanks woody21, got a couple if extra bodies available to help this week. What are your thoughts re the tightness of the polythene when fitting in 14-15 degrees and not on a warm day?

[VirginVegGrower]

We put ours on in that recent hot spell. It helps to stretch the plastic and get it nice and tight.

[Vince G]

Did mine in mid-March so that I could have a full summer growing season. It was about 15 degrees then and the skin is fine. It's not completely drum tight in places, but it'll survive whatever the British weather can chuck at it. I found the base at the end the most difficult bit. You seem to have so much plastic to batten onto the back of the door frame. I ended up trimming a bit off and still having plenty to secure against said frame.

Woody is right about the breeze. You need a lot of hands to keep the plastic under control or the thing will end up in Norway!

Don't know who you got yours from, but Citadel Polytunnels supplied me with enough timber to construct an 8 ft × 8ft brassica cage with the spare, and enough plastic to make a 15ft long 3ft high barrier for my carrots! Bonus!

Enjoy though, it's a brilliant investment. We've had a regular supply of cucumbers, lettuce and chillis since mid-May, and toms, peppers and aubergines won't be long. Plan now for growing stuff over the winter - being so far north, the light levels might be a bit of a problem for you but you can still grow stuff - read up on it. (Would seriously recommend you buy this book).

http://www.green-shopping.co.uk/how-...ear-round.html

I'm very envious, by the way. The most we're allowed at our lottie is 10 ft square, so a quarter the size of yours in total area. [grits teeth in jealous fashion...]

[Alison]

Did ours in Feb / March a few years ago and looking at the photos taken at the time it wasn't the warmest as we're well wrapped up. The skin is lovely and tight and I'd agree with the comments already made that a calm day is the important factor and apart from comfort for yourselves then the temperature doesn't really matter. Would try and get a dry day though as the polythene will be easier to hold etc.

[poly]

If you have the chance of fitting it on a calm day with a little sunshine, you'll find once you get the cover over the frame it will warm up inside really quickly which will help with relaxing the polythene and getting a good fit

Hope it goes well

[amandaandherveg]

Thanks so much everyone for the advice. It's from First Tunnels and I'm quite nervous about fitting the polythene - this is my first polytunnel and I'm trying so hard to get it right, it's a big jump from my old 8x6 polycarbonate greenhouse.. I'll keep you posted, perhaps even pics if I'm feeling brave.

[Newton]

I would expect that there will be some contraction in colder weather. Probably minimal though so getting it nice and tight in warm weather would allow for that. Don't know for sure though!

[OverWyreGrower]

We fitted our in 20mph winds (but it was quite warm!).... mind you, being on the coast means we always have a lot of winds...

We'd waited about 6 weeks for the weather to warm up/calm down for us to fit the plastic and it wasn't doing either, so we just did it anyway

As long as you've got someone to pull it as tight as you can, you should be fine

[First Tunnels Polytunnels]

The basis for fitting the polythene cover when the forecast is warm, calm weather ...(days which seem few and far between at the moment) is purely because the polythene will naturally stretch and fit more tightly as it shrinks when temperatures fall leaving a drum tight cover. However, as you have purchased base rails, you have the added bonus of re tensioning the cover should it appear “baggy”. The following step by step video shows how to fit the polythene cover Fitting the Polythene Cover - V28 - YouTube
All the very best

[amandaandherveg]

Thanks everyone, we managed to get the polytunnel covered on Thursday. It looks fantastic and we managed to get a drum tight fit with the base rails - it looks quite neat and tidy. It's so big and empty now, will have to get going with filling it up. Unfortunately it's been all of 7-9 degrees here the last two days with no sun and the tunnel is brrrrrrrrrr......freezing.

[poly]

Fabulous, happy planting . What have you got planned to grow?