Advice on the various forms of netting tunnels

[Stephen]

A variety of ready made tunnels of fleece, micromesh, netting and polythene are available.

Some of the differences are readily apparent, some are less discernable.
- polythene will keep rain off and probably lets most light through. You would need to move it to water.
- finer mesh will keep more small flies out
- netting is ok to keep birds off but presumably not flies. Does it keep butterflies out?
- how much difference is there between the heat retained by a fine/mircomesh tunnel and a fleece one?
- one can water through both micromesh and netting. I presume not with fleece.

Your expert views would be appreciated, being especially clear where you would NOT use one type. Suppliers are naturally keen to tell users of advantages of particular products, for understandable reasons they don't point out any disadvantages.

Thank you.

[tigerburnie]

From what I've seen it's not the covers that are the problem, it's the frames, I have had a couple with metal poles, but the connectors are made of plastic and break in the most modest of winds. I have made my frame from the blue water pipe, connected with bamboo you can then add the covering of your choice. I use mine to keep butterflies off the brassicas, works whilst the plants are small, but once the plants touch the sides the pesky butterflies can lay their eggs from outside the mesh. This year the tunnel will be on my strawberries to deter birds from pinching the fruit.
Water will pass through fleece and fleece will raise the temperature a bit by reducing the wind passing through, fine mesh will also keep the temperature up a little bit, but the mesh will not stop a frost whereas fleece will.

[Stephen]

Thanks Tiger
The general advice is helpful but I was specifically thinking about this sort of thing:

or

[tigerburnie]

I find those type are a bit too small and the crops then touch the netting and are open to attack, hence the bigger tunnel made from blue water pipe. When mine is erected in the next few weeks, I'll take a photo, I do use similar netting to your second picture