Topic: Will this work? Plastic covers on raised beds to create mini poly tunnels?

[Crystalmoon]

Hi everyone, I usually dont grow veg on my allotment during the winter as my arthritis gets so bad but this year I am going to try my best.....I dont have a poly tunnel but have been covering my small raised beds with thick plastic sheeting to make mini tunnels. The beds are the plastic sort that help to keep the soil warm & I have filled them with soft compost rather than the rock hard clay my lotty is made of. I am planning to attempt to grow winter lettuce & other plants that need to be under cover during the winter (seedlings are in a platic greenhouse at home at the moment) but it feels so cold tonight Im wondering if Im just kidding myself that it will work ok. As I have no experience of poly tunnels  I am assuming they are unheated? This may well be a very stupid question but when a seed packet says ok in winter under cover does that mean in an unheated tunnel? Thanks x Jane

[pumkinlover]

Something I've been wondering :-X

[Crystalmoon]

Glad Im not the only one :D the seed packets are so vague....under cover could mean in a greenhouse! Sigh xJane

[ru2010]

Hi Jane,

I think your covered raised beds will work exactly like a greenhouse - a greenhouse, after all, is just a layer of glass or plastic between the plants and the elements!

You could always get a couple of thermometers and measure the respective temperatures of your beds and the outside world - you could post the results on here over a few weeks period, it would be interesting to see how much difference there is.

So, bung your seeds in and see what happens.

[lottie lou]

Thought I'd let you know, I grew lettuce last winter, albeit slowly, under plastic water bottles.  Just cut the bottoms off, put over plant and shove a stick through the open top to hold it in place.  If you do that underneath the poly it would be double insulation don't you think.

[Digeroo]

I grow peas and lettuce under plastic bottles, then if real cold is forecast then I throw over a piece of fleece and a plastic sheet.    It the plants touch the plastic they tend to rot or get frosted.  It may be tempting to leave the top on the plastic bottle but the plants need the air.  They lasted all through last winter.    If you have something more tender put a plastic bottle almost full of water next to the plants.  I have had good results with a couple of rows of plastic bottles full of water buried about 25% into the soil and then put plastic over the top.  The bottles keep the plastic off the plants.  A few stick put into the soil around the bottles stops them being blown over.

[GrannieAnnie]

I've grown loose-leaf lettuce "Red Sails" under a window, the window being held up off the soil and lettuce by some bricks piled up at each corner. This was placed in a raised bed which is about 2 inches above ground. Even with the wind blowing in the plants didn't die. I germinated the seeds in end of Aug. which is still very hot here in Delaware. The plants are now big and bushy. We've already had frost and some snow! I must raise the pile of bricks more because the leaves are touching the glass and as mentioned will rot if they touch.  As it gets very cold the growth slows down with this open method, then picks up again rapidly in Feb/March. I read it is better not to fertilize in the winter.

Choose a type lettuce that doesn't mind cold. I also have some sort of Chinese greens which are doing very well and are more peppery though cannot remember the type and didn't write it down ::) The idea of planting under a bottle sounds worth a try, too.

[Crystalmoon]

Hi everyone  :) Sofar the plants are doing great uinder the plastic covers. The plastic bottles & window ideas have got me thinking about what other plants I can attempt to grow this winter, thanks for the geat ideas xjane